[OOM-CMPv2] Rename module folder truststoreMerger -> certServicePostProcessor

Issue-ID: DCAEGEN2-2253
Signed-off-by: Jan Malkiewicz <jan.malkiewicz@nokia.com>
Change-Id: I975f37507f7f79c238f1eac15f375fe64761c80c

42 files changed, 1985 insertions, 0 deletions

diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExecutor.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExecutor.java
new file mode 100644
index 00000000..2ef30b68
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExecutor.java
@@ -0,0 +1,54 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class AppExecutor {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(AppExecutor.class);
+
+    private AppExitHandler exitHandler;
+
+    AppExecutor() {
+        this(new AppExitHandler());
+    }
+
+    AppExecutor(AppExitHandler exitHandler) {
+        this.exitHandler = exitHandler;
+    }
+
+
+    public void execute(Runnable logic) {
+        try {
+            logic.run();
+            exitHandler.exit(ExitStatus.SUCCESS);
+        } catch (ExitableException e) {
+            LOGGER.error("Application failed: ", e);
+            exitHandler.exit(e.applicationExitStatus());
+        } catch (Exception e) {
+            LOGGER.error("Application failed (unexpected error): ", e);
+            exitHandler.exit(ExitStatus.UNEXPECTED_EXCEPTION);
+        }
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExitHandler.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExitHandler.java
new file mode 100644
index 00000000..15677dc4
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/AppExitHandler.java
@@ -0,0 +1,34 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class AppExitHandler {
+    private static final Logger LOGGER = LoggerFactory.getLogger(AppExitHandler.class);
+
+    public void exit(ExitStatus exitStatus) {
+        LOGGER.info("Application exits with code [{}] and message: {}",
+                exitStatus.getExitCodeValue(), exitStatus.getMessage());
+        System.exit(exitStatus.getExitCodeValue());
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/CertificatePostProcessor.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/CertificatePostProcessor.java
new file mode 100644
index 00000000..b9038227
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/CertificatePostProcessor.java
@@ -0,0 +1,47 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor;
+
+import org.onap.oom.certservice.postprocessor.common.FileTools;
+import org.onap.oom.certservice.postprocessor.configuration.AppConfigurationLoader;
+import org.onap.oom.certservice.postprocessor.configuration.model.AppConfiguration;
+import org.onap.oom.certservice.postprocessor.copier.KeystoreCopier;
+import org.onap.oom.certservice.postprocessor.merger.TruststoreMerger;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+class CertificatePostProcessor implements Runnable {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(CertificatePostProcessor.class);
+
+    private AppConfigurationLoader config = new AppConfigurationLoader();
+    private TruststoreMerger merger = new TruststoreMerger();
+    private KeystoreCopier copier = new KeystoreCopier(new FileTools());
+
+    public void run() {
+        LOGGER.debug("Loading configuration...");
+        AppConfiguration configuration = config.loadConfiguration();
+        LOGGER.debug("Starting TruststoreMerger...");
+        merger.mergeTruststores(configuration);
+        LOGGER.debug("Starting KeystoreCopier...");
+        copier.copyKeystores(configuration);
+        LOGGER.debug("Certificate post processing finished successfully.");
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/MainApp.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/MainApp.java
new file mode 100644
index 00000000..f815f489
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/MainApp.java
@@ -0,0 +1,27 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor;
+
+public class MainApp {
+
+    public static void main(String[] args) {
+        new AppExecutor().execute(new CertificatePostProcessor());
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/CertificateConstants.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/CertificateConstants.java
new file mode 100644
index 00000000..3442621b
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/CertificateConstants.java
@@ -0,0 +1,31 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.api;
+
+public class CertificateConstants {
+
+    private CertificateConstants() { }
+
+    public static final String JKS_TYPE = "JKS";
+    public static final String PKCS12_TYPE = "PKCS12";
+    public static final String X_509_CERTIFICATE = "X.509";
+    public static final String BOUNCY_CASTLE_PROVIDER = "BC";
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitStatus.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitStatus.java
new file mode 100644
index 00000000..b6cebeb1
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitStatus.java
@@ -0,0 +1,56 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.api;
+
+public enum ExitStatus {
+
+    SUCCESS(0, "Success"),
+    CERTIFICATES_PATHS_VALIDATION_EXCEPTION(1, "Invalid paths in environment variables"),
+    CONFIGURATION_EXCEPTION(2, "Invalid merger configuration"),
+    TRUSTSTORE_FILE_FACTORY_EXCEPTION(3, "Invalid truststore file-password pair"),
+    PASSWORD_READER_EXCEPTION(4, "Cannot read password from file"),
+    CREATE_BACKUP_EXCEPTION(5, "Cannot create backup file"),
+    KEYSTORE_INSTANCE_EXCEPTION(6, "Cannot initialize keystore instance"),
+    TRUSTSTORE_LOAD_FILE_EXCEPTION(7, "Cannot load truststore file"),
+    TRUSTSTORE_DATA_OPERATION_EXCEPTION(8, "Cannot operate on truststore data"),
+    MISSING_TRUSTSTORE_EXCEPTION(9, "Missing truststore certificates in provided file"),
+    ALIAS_CONFLICT_EXCEPTION(10, "Alias conflict detected"),
+    WRITE_TRUSTSTORE_FILE_EXCEPTION(11, "Cannot save truststore file"),
+    KEYSTORE_FILE_COPY_EXCEPTION(12, "Cannot copy keystore file"),
+    KEYSTORE_NOT_EXIST_EXCEPTION(13, "Keystore file does not exist"),
+    UNEXPECTED_EXCEPTION(99, "Application exited abnormally");
+
+
+    private final int value;
+    private final String message;
+
+    ExitStatus(int value, String message) {
+        this.value = value;
+        this.message = message;
+    }
+
+    public int getExitCodeValue() {
+        return value;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitableException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitableException.java
new file mode 100644
index 00000000..54a7c6a1
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/api/ExitableException.java
@@ -0,0 +1,40 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.api;
+
+public class ExitableException extends RuntimeException {
+
+    private final ExitStatus exitStatus;
+
+    public ExitableException(Throwable cause, ExitStatus exitStatus) {
+        super(cause);
+        this.exitStatus = exitStatus;
+    }
+
+    public ExitableException(String message, ExitStatus exitStatus) {
+        super(message);
+        this.exitStatus = exitStatus;
+    }
+
+    public ExitStatus applicationExitStatus() {
+        return exitStatus;
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/ExtensionResolver.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/ExtensionResolver.java
new file mode 100644
index 00000000..7a785ae1
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/ExtensionResolver.java
@@ -0,0 +1,42 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.common;
+
+import java.io.File;
+
+public final class ExtensionResolver {
+
+    private static final int INDEX_NOT_FOUND = -1;
+
+    private ExtensionResolver() {}
+
+    public static String get(File file) {
+        int extStartIndex = file.getName().lastIndexOf(".");
+        if (extStartIndex == INDEX_NOT_FOUND) {
+            return "";
+        }
+        return file.getName().substring(extStartIndex).toLowerCase();
+    }
+
+    public static boolean checkIfFileExists(File file) {
+        return file.exists();
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/FileTools.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/FileTools.java
new file mode 100644
index 00000000..620d8088
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/FileTools.java
@@ -0,0 +1,52 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.common;
+
+import java.io.File;
+import java.io.IOException;
+import org.apache.commons.io.FileUtils;
+import org.onap.oom.certservice.postprocessor.merger.exception.CreateBackupException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class FileTools {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(FileTools.class);
+    private static final String BACKUP_EXTENSION = ".bak";
+
+    public void createBackup(File file) throws CreateBackupException {
+        LOGGER.debug("Try to create a backup of the file: {}", file.getPath());
+        File backupFile = new File(file.getAbsolutePath() + BACKUP_EXTENSION);
+        try  {
+            copy(file, backupFile);
+        } catch (IOException e) {
+            LOGGER.error("Could not create backup of the file: '{}'", file.getPath());
+            throw new CreateBackupException(e);
+        }
+        LOGGER.debug("Backup file created: '{}'", backupFile.getAbsolutePath());
+    }
+
+    public void copy(File source, File destination) throws IOException {
+        LOGGER.debug("Try to copy from '{}' to '{}'.", source.getAbsolutePath(), destination.getAbsolutePath());
+        FileUtils.copyFile(source, destination);
+        LOGGER.debug("File copied from '{}' to '{}'.", source.getAbsolutePath(),
+            destination.getAbsolutePath());
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/PasswordReader.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/PasswordReader.java
new file mode 100644
index 00000000..6e4a5f3a
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/common/PasswordReader.java
@@ -0,0 +1,41 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.common;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import org.onap.oom.certservice.postprocessor.merger.exception.PasswordReaderException;
+
+public final class PasswordReader {
+
+    private static final String COULD_NOT_READ_PASSWORD_FROM_FILE_MSG_TEMPLATE = "Could not read password from file: %s";
+
+    private PasswordReader() {
+    }
+
+    public static String readPassword(File file) {
+        try {
+            return Files.readString(file.toPath());
+        } catch (IOException e) {
+            throw new PasswordReaderException(String.format(COULD_NOT_READ_PASSWORD_FROM_FILE_MSG_TEMPLATE, file));
+        }
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationLoader.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationLoader.java
new file mode 100644
index 00000000..a3f49d86
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationLoader.java
@@ -0,0 +1,33 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration;
+
+import org.onap.oom.certservice.postprocessor.configuration.model.AppConfiguration;
+import org.onap.oom.certservice.postprocessor.configuration.path.DelimitedPathsSplitter;
+import org.onap.oom.certservice.postprocessor.configuration.path.env.EnvReader;
+
+public class AppConfigurationLoader {
+
+    public AppConfiguration loadConfiguration() {
+        DelimitedPathsSplitter pathsSplitter = new DelimitedPathsSplitter();
+        AppConfigurationProvider factory = new AppConfigurationProvider(pathsSplitter, new EnvReader());
+        return factory.createConfiguration();
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationProvider.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationProvider.java
new file mode 100644
index 00000000..1e9ef8a9
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/AppConfigurationProvider.java
@@ -0,0 +1,82 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration;
+
+
+import static org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable.KEYSTORE_DESTINATION_PATHS;
+import static org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable.KEYSTORE_SOURCE_PATHS;
+import static org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable.TRUSTSTORES_PASSWORDS_PATHS;
+import static org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable.TRUSTSTORES_PATHS;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+import org.onap.oom.certservice.postprocessor.configuration.path.env.EnvReader;
+import org.onap.oom.certservice.postprocessor.configuration.exception.ConfigurationException;
+import org.onap.oom.certservice.postprocessor.configuration.model.AppConfiguration;
+import org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable;
+import org.onap.oom.certservice.postprocessor.configuration.path.DelimitedPathsSplitter;
+
+public class AppConfigurationProvider {
+
+    private final EnvReader envReader;
+    private final DelimitedPathsSplitter pathsSplitter;
+
+    public AppConfigurationProvider(DelimitedPathsSplitter pathsSplitter, EnvReader envReader) {
+        this.envReader = envReader;
+        this.pathsSplitter = pathsSplitter;
+    }
+
+    public AppConfiguration createConfiguration() {
+        List<String> truststoresPaths = getPaths(TRUSTSTORES_PATHS);
+        List<String> truststoresPasswordsPaths = getPaths(TRUSTSTORES_PASSWORDS_PATHS);
+        List<String> sourceKeystorePaths = getPaths(KEYSTORE_SOURCE_PATHS);
+        List<String> destinationKeystorePaths = getPaths(KEYSTORE_DESTINATION_PATHS);
+
+        ensureSameSize(truststoresPaths, truststoresPasswordsPaths, TRUSTSTORES_PATHS.name(),
+            TRUSTSTORES_PASSWORDS_PATHS.name());
+        ensureSameSize(sourceKeystorePaths, destinationKeystorePaths, KEYSTORE_SOURCE_PATHS.name(),
+            KEYSTORE_DESTINATION_PATHS.name());
+
+        return new AppConfiguration(truststoresPaths, truststoresPasswordsPaths, sourceKeystorePaths,
+            destinationKeystorePaths);
+    }
+
+    private List<String> getPaths(EnvVariable envVariable) {
+        Optional<String> envValue = envReader.getEnv(envVariable.name());
+        isMandatoryEnvPresent(envVariable, envValue);
+        return envValue.isPresent() ? pathsSplitter.getValidatedPaths(envVariable, envValue) : Collections.emptyList();
+    }
+
+    private void isMandatoryEnvPresent(EnvVariable envVariable, Optional<String> envValue) {
+        if (envVariable.isMandatory() && envValue.isEmpty()) {
+            throw new ConfigurationException(envVariable + " mandatory environment variable is not defined");
+        }
+    }
+
+    private void ensureSameSize(List<String> firstList, List<String> secondList, String firstListEnvName,
+                                String secondListEnvName) {
+        if (firstList.size() != secondList.size()) {
+            throw new ConfigurationException(
+                "Size of " + firstListEnvName
+                    + " does not match size of " + secondListEnvName + " environment variables");
+        }
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/CertificatesPathsValidationException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/CertificatesPathsValidationException.java
new file mode 100644
index 00000000..fb621017
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/CertificatesPathsValidationException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class CertificatesPathsValidationException extends ExitableException {
+
+    public CertificatesPathsValidationException(String errorMessage) {
+        super(errorMessage, ExitStatus.CERTIFICATES_PATHS_VALIDATION_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/ConfigurationException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/ConfigurationException.java
new file mode 100644
index 00000000..c9f9a416
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/exception/ConfigurationException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class ConfigurationException extends ExitableException {
+
+    public ConfigurationException(String errorMessage) {
+        super(errorMessage, ExitStatus.CONFIGURATION_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/AppConfiguration.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/AppConfiguration.java
new file mode 100644
index 00000000..d28dcac5
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/AppConfiguration.java
@@ -0,0 +1,56 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.model;
+
+import java.util.Collections;
+import java.util.List;
+
+public final class AppConfiguration {
+    private final List<String> truststoreFilePaths;
+    private final List<String> truststoreFilePasswordPaths;
+    private final List<String> sourceKeystorePaths;
+    private final List<String> destinationKeystorePaths;
+
+    public AppConfiguration(List<String> truststoreFilePaths,
+        List<String> truststoreFilePasswordPaths, List<String> sourceKeystorePaths,
+        List<String> destinationKeystorePaths) {
+        this.truststoreFilePaths = List.copyOf(truststoreFilePaths);
+        this.truststoreFilePasswordPaths = List.copyOf(truststoreFilePasswordPaths);
+        this.sourceKeystorePaths = List.copyOf(sourceKeystorePaths);
+        this.destinationKeystorePaths = List.copyOf(destinationKeystorePaths);
+    }
+
+    public List<String> getTruststoreFilePaths() {
+        return Collections.unmodifiableList(truststoreFilePaths);
+    }
+
+    public List<String> getTruststoreFilePasswordPaths() {
+        return Collections.unmodifiableList(truststoreFilePasswordPaths);
+    }
+
+
+    public List<String> getDestinationKeystorePaths() {
+        return Collections.unmodifiableList(destinationKeystorePaths);
+    }
+
+    public List<String> getSourceKeystorePaths() {
+        return Collections.unmodifiableList(sourceKeystorePaths);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/EnvVariable.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/EnvVariable.java
new file mode 100644
index 00000000..be49d39c
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/model/EnvVariable.java
@@ -0,0 +1,51 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.model;
+
+import static org.onap.oom.certservice.postprocessor.configuration.path.validation.ValidationFunctions.doesItContainValidCertificatesPaths;
+import static org.onap.oom.certservice.postprocessor.configuration.path.validation.ValidationFunctions.doesItContainValidPasswordPaths;
+import static org.onap.oom.certservice.postprocessor.configuration.path.validation.ValidationFunctions.doesItContainValidPathsToCopy;
+
+import java.util.List;
+import java.util.function.Predicate;
+
+public enum EnvVariable {
+    TRUSTSTORES_PATHS(true, doesItContainValidCertificatesPaths()),
+    TRUSTSTORES_PASSWORDS_PATHS(true, doesItContainValidPasswordPaths()),
+    KEYSTORE_SOURCE_PATHS(false, doesItContainValidPathsToCopy()),
+    KEYSTORE_DESTINATION_PATHS(false, doesItContainValidPathsToCopy());
+
+    boolean isMandatory;
+
+    Predicate<List<String>> validationFunction;
+
+    EnvVariable(boolean isMandatory, Predicate<List<String>> validationFunction) {
+        this.isMandatory = isMandatory;
+        this.validationFunction = validationFunction;
+    }
+
+    public boolean isMandatory() {
+        return isMandatory;
+    }
+
+    public Predicate<List<String>> getValidationFunction() {
+        return validationFunction;
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/DelimitedPathsSplitter.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/DelimitedPathsSplitter.java
new file mode 100644
index 00000000..b2e71cb3
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/DelimitedPathsSplitter.java
@@ -0,0 +1,49 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.path;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+import org.onap.oom.certservice.postprocessor.configuration.exception.CertificatesPathsValidationException;
+import org.onap.oom.certservice.postprocessor.configuration.model.EnvVariable;
+
+public class DelimitedPathsSplitter {
+
+    private static final String DELIMITER = ":";
+    private static final int NEGATIVE_SPLIT_LIMIT = -1;
+
+    public List<String> getValidatedPaths(EnvVariable envVariable, Optional<String> envValue)
+        throws CertificatesPathsValidationException {
+        return envValue.filter(this::hasValue)
+            .map(this::splitToList)
+            .filter(envVariable.getValidationFunction())
+            .orElseThrow(() -> new CertificatesPathsValidationException(
+                envVariable + " environment variable does not contain valid paths"));
+    }
+
+    private boolean hasValue(String envValue) {
+        return !envValue.isEmpty();
+    }
+
+    private List<String> splitToList(String stringToSplit) {
+        return Arrays.asList(stringToSplit.split(DELIMITER, NEGATIVE_SPLIT_LIMIT));
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/env/EnvReader.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/env/EnvReader.java
new file mode 100644
index 00000000..f30e43be
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/env/EnvReader.java
@@ -0,0 +1,39 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.path.env;
+
+import java.util.Optional;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class EnvReader {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(EnvReader.class);
+
+    public Optional<String> getEnv(String name) {
+        return getSystemEnv(name);
+    }
+
+    Optional<String> getSystemEnv(String name) {
+        String value = System.getenv(name);
+        LOGGER.info("Read variable: {} , value: {}", name, value);
+        return Optional.ofNullable(value);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/validation/ValidationFunctions.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/validation/ValidationFunctions.java
new file mode 100644
index 00000000..f65a21a0
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/configuration/path/validation/ValidationFunctions.java
@@ -0,0 +1,57 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.configuration.path.validation;
+
+import java.util.List;
+import java.util.function.Predicate;
+
+public final class ValidationFunctions {
+
+    private static final String CERTIFICATE_PATH_REGEX = "^(/[a-zA-Z0-9_-]+)+\\.(pem|jks|p12)";
+    private static final String CERTIFICATE_PASSWORD_PATH_REGEX = "^(/[a-zA-Z0-9_-]+)+\\.pass";
+
+    private ValidationFunctions() {
+    }
+
+    public static Predicate<List<String>> doesItContainValidPasswordPaths() {
+        return paths -> paths.stream().allMatch(ValidationFunctions::isCertificatePasswordPathValid);
+    }
+
+    public static Predicate<List<String>> doesItContainValidCertificatesPaths() {
+        return paths -> paths.stream().allMatch(ValidationFunctions::isCertificatePathValid);
+    }
+
+    public static Predicate<List<String>> doesItContainValidPathsToCopy() {
+        return paths -> paths.stream().allMatch(path ->
+            doesMatch(path, CERTIFICATE_PASSWORD_PATH_REGEX) || isCertificatePathValid(path));
+    }
+
+    private static boolean isCertificatePathValid(String path) {
+        return doesMatch(path, CERTIFICATE_PATH_REGEX);
+    }
+
+    private static boolean isCertificatePasswordPathValid(String path) {
+        return path.isEmpty() || doesMatch(path, CERTIFICATE_PASSWORD_PATH_REGEX);
+    }
+
+    private static boolean doesMatch(String path, String regex) {
+        return path.matches(regex);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/KeystoreCopier.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/KeystoreCopier.java
new file mode 100644
index 00000000..f5cea212
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/KeystoreCopier.java
@@ -0,0 +1,74 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.copier;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+import org.onap.oom.certservice.postprocessor.common.FileTools;
+import org.onap.oom.certservice.postprocessor.configuration.model.AppConfiguration;
+import org.onap.oom.certservice.postprocessor.copier.exception.KeystoreFileCopyException;
+import org.onap.oom.certservice.postprocessor.copier.exception.KeystoreNotExistException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class KeystoreCopier {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(KeystoreCopier.class);
+    private final FileTools fileTools;
+
+    public KeystoreCopier(FileTools fileTools) {
+        this.fileTools = fileTools;
+    }
+
+    public void copyKeystores(AppConfiguration configuration) {
+        final List<String> sources = configuration.getSourceKeystorePaths();
+        final List<String> destinations = configuration.getDestinationKeystorePaths();
+        containsPaths(sources);
+        try {
+            for (int i = 0; i < sources.size(); i++) {
+                copy(sources.get(i), destinations.get(i));
+            }
+        } catch (IOException e) {
+            throw new KeystoreFileCopyException(e);
+        }
+    }
+
+    private void containsPaths(List<String> sources) {
+        if (sources.isEmpty()) {
+            LOGGER.info("No Keystore files to copy");
+        }
+    }
+
+    private void copy(String sourcePath, String destinationPath) throws IOException {
+        final File source = new File(sourcePath);
+        final File destination = new File(destinationPath);
+
+        if (!source.exists()) {
+            throw new KeystoreNotExistException("Keystore file does not exist '" + source.getAbsolutePath() + "'!");
+        }
+
+        if (destination.exists()) {
+            fileTools.createBackup(destination);
+        }
+        fileTools.copy(source, destination);
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreFileCopyException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreFileCopyException.java
new file mode 100644
index 00000000..66190965
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreFileCopyException.java
@@ -0,0 +1,31 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.copier.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class KeystoreFileCopyException extends ExitableException {
+
+    public KeystoreFileCopyException(Exception e) {
+        super(e, ExitStatus.KEYSTORE_FILE_COPY_EXCEPTION);
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreNotExistException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreNotExistException.java
new file mode 100644
index 00000000..37f2f537
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/copier/exception/KeystoreNotExistException.java
@@ -0,0 +1,31 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.copier.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class KeystoreNotExistException extends ExitableException {
+
+    public KeystoreNotExistException(String message) {
+        super(message, ExitStatus.KEYSTORE_NOT_EXIST_EXCEPTION);
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreFilesProvider.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreFilesProvider.java
new file mode 100644
index 00000000..9e30bd44
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreFilesProvider.java
@@ -0,0 +1,46 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.onap.oom.certservice.postprocessor.merger.model.Truststore;
+import org.onap.oom.certservice.postprocessor.merger.model.TruststoreFactory;
+
+public class TruststoreFilesProvider {
+
+
+    private TruststoreFilesProvider() {
+    }
+
+    public static List<Truststore> getTruststoreFiles(List<String> truststoreFilePaths,
+                                                      List<String> truststoreFilePasswordPaths) {
+        List<Truststore> truststoreFiles = new ArrayList<>();
+        for (int i = 0; i < truststoreFilePaths.size(); i++) {
+            String truststorePath = truststoreFilePaths.get(i);
+            String passwordPath = truststoreFilePasswordPaths.get(i);
+
+            Truststore truststore = TruststoreFactory.create(truststorePath, passwordPath);
+            truststoreFiles.add(truststore);
+        }
+
+        return truststoreFiles;
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreMerger.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreMerger.java
new file mode 100644
index 00000000..3cf60da1
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/TruststoreMerger.java
@@ -0,0 +1,54 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger;
+
+import java.util.List;
+import org.onap.oom.certservice.postprocessor.configuration.model.AppConfiguration;
+import org.onap.oom.certservice.postprocessor.merger.model.Truststore;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAlias;
+
+public class TruststoreMerger {
+
+    private static final int FIRST_TRUSTSTORE_INDEX = 0;
+    private static final int SECOND_TRUSTSTORE_INDEX = 1;
+
+    public void mergeTruststores(AppConfiguration configuration) {
+        List<Truststore> truststoreFilesList = getTruststoreFiles(configuration);
+
+        Truststore baseFile = truststoreFilesList.get(FIRST_TRUSTSTORE_INDEX);
+        baseFile.createBackup();
+
+        for (int i = SECOND_TRUSTSTORE_INDEX; i < truststoreFilesList.size(); i++) {
+            Truststore truststore = truststoreFilesList.get(i);
+            List<CertificateWithAlias> certificateWrappers = truststore.getCertificates();
+            baseFile.addCertificates(certificateWrappers);
+        }
+
+        baseFile.saveFile();
+    }
+
+    private List<Truststore> getTruststoreFiles(AppConfiguration configuration) {
+        return TruststoreFilesProvider
+            .getTruststoreFiles(
+                configuration.getTruststoreFilePaths(),
+                configuration.getTruststoreFilePasswordPaths()
+            );
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/AliasConflictException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/AliasConflictException.java
new file mode 100644
index 00000000..2e7939b7
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/AliasConflictException.java
@@ -0,0 +1,31 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class AliasConflictException extends ExitableException {
+
+    public AliasConflictException(String errorMessage) {
+        super(errorMessage, ExitStatus.ALIAS_CONFLICT_EXCEPTION);
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/CreateBackupException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/CreateBackupException.java
new file mode 100644
index 00000000..8e99f993
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/CreateBackupException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class CreateBackupException extends ExitableException {
+
+    public CreateBackupException(Exception cause) {
+        super(cause, ExitStatus.CREATE_BACKUP_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/KeystoreInstanceException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/KeystoreInstanceException.java
new file mode 100644
index 00000000..1279dff7
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/KeystoreInstanceException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class KeystoreInstanceException extends ExitableException {
+
+    public KeystoreInstanceException(Exception cause) {
+        super(cause, ExitStatus.KEYSTORE_INSTANCE_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/LoadTruststoreException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/LoadTruststoreException.java
new file mode 100644
index 00000000..b3493fd6
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/LoadTruststoreException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class LoadTruststoreException extends ExitableException {
+
+    public LoadTruststoreException(Exception cause) {
+        super(cause, ExitStatus.TRUSTSTORE_LOAD_FILE_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/MissingTruststoreException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/MissingTruststoreException.java
new file mode 100644
index 00000000..51660f60
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/MissingTruststoreException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class MissingTruststoreException extends ExitableException {
+
+    public MissingTruststoreException(String errorMessage) {
+        super(errorMessage, ExitStatus.MISSING_TRUSTSTORE_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/PasswordReaderException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/PasswordReaderException.java
new file mode 100644
index 00000000..b1bdf1ea
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/PasswordReaderException.java
@@ -0,0 +1,29 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class PasswordReaderException extends ExitableException {
+    public PasswordReaderException(String errorMessage) {
+        super(errorMessage, ExitStatus.PASSWORD_READER_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreDataOperationException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreDataOperationException.java
new file mode 100644
index 00000000..77ae366e
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreDataOperationException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class TruststoreDataOperationException extends ExitableException {
+
+    public TruststoreDataOperationException(Exception cause) {
+        super(cause, ExitStatus.TRUSTSTORE_DATA_OPERATION_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreFileFactoryException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreFileFactoryException.java
new file mode 100644
index 00000000..a87a62a3
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/TruststoreFileFactoryException.java
@@ -0,0 +1,30 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class TruststoreFileFactoryException extends ExitableException {
+    public TruststoreFileFactoryException(String errorMessage) {
+        super(errorMessage, ExitStatus.TRUSTSTORE_FILE_FACTORY_EXCEPTION);
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/WriteTruststoreFileException.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/WriteTruststoreFileException.java
new file mode 100644
index 00000000..f9b772ca
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/exception/WriteTruststoreFileException.java
@@ -0,0 +1,31 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+
+package org.onap.oom.certservice.postprocessor.merger.exception;
+
+import org.onap.oom.certservice.postprocessor.api.ExitStatus;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+
+public class WriteTruststoreFileException extends ExitableException {
+
+    public WriteTruststoreFileException(Exception cause) {
+        super(cause, ExitStatus.WRITE_TRUSTSTORE_FILE_EXCEPTION);
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststore.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststore.java
new file mode 100644
index 00000000..d264d2f4
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststore.java
@@ -0,0 +1,166 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.security.KeyStore;
+import java.security.KeyStoreException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import org.onap.oom.certservice.postprocessor.merger.exception.AliasConflictException;
+import org.onap.oom.certservice.postprocessor.merger.exception.LoadTruststoreException;
+import org.onap.oom.certservice.postprocessor.merger.exception.MissingTruststoreException;
+import org.onap.oom.certservice.postprocessor.merger.exception.TruststoreDataOperationException;
+import org.onap.oom.certservice.postprocessor.merger.exception.WriteTruststoreFileException;
+import org.onap.oom.certservice.postprocessor.api.ExitableException;
+import org.onap.oom.certservice.postprocessor.common.FileTools;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAlias;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAliasFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class JavaTruststore extends Truststore {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(JavaTruststore.class);
+
+    private final CertificateWithAliasFactory factory = new CertificateWithAliasFactory();
+    private final KeyStore keyStore;
+    private final String password;
+
+
+    private JavaTruststore(KeyStore keyStore, File storeFile, String password) {
+        super(storeFile, new FileTools());
+        this.keyStore = keyStore;
+        this.password = password;
+    }
+
+    public static JavaTruststore createWithLoadingFile(KeyStore keyStore, File storeFile, String password)
+        throws LoadTruststoreException {
+        JavaTruststore javaTruststore = new JavaTruststore(keyStore, storeFile, password);
+        javaTruststore.loadFile();
+        return javaTruststore;
+    }
+
+    public List<CertificateWithAlias> getCertificates() throws ExitableException {
+        LOGGER.debug("Attempt to read certificates from file: {}", storeFile.getPath());
+        List<String> aliases = getTruststoreAliases();
+        if (aliases.isEmpty()) {
+            throw new MissingTruststoreException("Missing certificate aliases in file: " + storeFile.getPath());
+        }
+        return getWrappedCertificates(aliases);
+    }
+
+    public void addCertificates(List<CertificateWithAlias> certificatesWithAliases)
+        throws ExitableException {
+        LOGGER.debug("Attempt to add certificates for saving to file");
+        if (getTruststoreAliases().isEmpty()) {
+            throw new MissingTruststoreException("Missing certificate aliases in file: " + storeFile.getPath());
+        }
+        for (CertificateWithAlias certificate : certificatesWithAliases) {
+            addCertificate(certificate);
+        }
+    }
+
+    public void saveFile() throws WriteTruststoreFileException {
+        LOGGER.debug("Attempt to save file: {}", storeFile.getPath());
+        try (FileOutputStream outputStream = new FileOutputStream(storeFile)) {
+            keyStore.store(outputStream, this.password.toCharArray());
+        } catch (Exception e) {
+            LOGGER.error("Cannot write truststore file");
+            throw new WriteTruststoreFileException(e);
+        }
+    }
+
+    private void loadFile() throws LoadTruststoreException {
+        try {
+            keyStore.load(new FileInputStream(storeFile), this.password.toCharArray());
+        } catch (Exception e) {
+            LOGGER.error("Cannot load file: {}", storeFile.getPath());
+            throw new LoadTruststoreException(e);
+        }
+    }
+
+    private void addCertificate(CertificateWithAlias certificate)
+        throws TruststoreDataOperationException, AliasConflictException {
+        if (hasAliasConflict(certificate)) {
+            LOGGER.error("Alias conflict detected");
+            throw new AliasConflictException("Alias conflict detected. Alias conflicted: " + certificate.getAlias());
+        }
+        try {
+            keyStore.setCertificateEntry(certificate.getAlias(), certificate.getCertificate());
+        } catch (KeyStoreException e) {
+            LOGGER.error("Cannot merge certificate with alias: {}", certificate.getAlias());
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private boolean hasAliasConflict(CertificateWithAlias certificate) throws TruststoreDataOperationException {
+        try {
+            return keyStore.containsAlias(certificate.getAlias());
+        } catch (KeyStoreException e) {
+            LOGGER.error("Cannot check alias conflict");
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private List<CertificateWithAlias> getWrappedCertificates(List<String> aliases)
+        throws TruststoreDataOperationException {
+
+        List<CertificateWithAlias> certificateWrapped = new ArrayList<>();
+
+        for (String alias : aliases) {
+            certificateWrapped.add(createWrappedCertificate(alias));
+        }
+        return certificateWrapped;
+    }
+
+    private CertificateWithAlias createWrappedCertificate(String alias) throws TruststoreDataOperationException {
+        try {
+            return factory.createCertificateWithAlias(keyStore.getCertificate(alias), alias);
+        } catch (KeyStoreException e) {
+            LOGGER.warn("Cannot get certificate with alias: {} ", alias);
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private List<String> getTruststoreAliases() throws TruststoreDataOperationException {
+        try {
+            List<String> aliases = Collections.list(keyStore.aliases());
+            return getFilteredAlias(aliases);
+        } catch (KeyStoreException e) {
+            LOGGER.warn("Cannot read truststore aliases");
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private List<String> getFilteredAlias(List<String> aliases) throws KeyStoreException {
+        List<String> filteredAlias = new ArrayList<>();
+        for (String alias : aliases) {
+            if (keyStore.isCertificateEntry(alias)) {
+                filteredAlias.add(alias);
+            }
+        }
+        return filteredAlias;
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststoreFactory.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststoreFactory.java
new file mode 100644
index 00000000..4740d0f6
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/JavaTruststoreFactory.java
@@ -0,0 +1,48 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model;
+
+import java.io.File;
+import java.security.KeyStore;
+import java.security.KeyStoreException;
+import org.onap.oom.certservice.postprocessor.merger.exception.KeystoreInstanceException;
+import org.onap.oom.certservice.postprocessor.common.PasswordReader;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class JavaTruststoreFactory {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(JavaTruststoreFactory.class);
+
+    private JavaTruststoreFactory() {
+    }
+
+    public static Truststore create(File certFile, String truststorePasswordPath, String keystoreType) {
+        String password = PasswordReader.readPassword(new File(truststorePasswordPath));
+        try {
+            return JavaTruststore
+                .createWithLoadingFile(KeyStore.getInstance(keystoreType), certFile, password);
+        } catch (KeyStoreException e) {
+            LOGGER.error("Cannot initialize Java Keystore instance");
+            throw new KeystoreInstanceException(e);
+        }
+    }
+}
+
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/PemTruststore.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/PemTruststore.java
new file mode 100644
index 00000000..d7f4bfd2
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/PemTruststore.java
@@ -0,0 +1,156 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model;
+
+import static org.onap.oom.certservice.postprocessor.api.CertificateConstants.BOUNCY_CASTLE_PROVIDER;
+import static org.onap.oom.certservice.postprocessor.api.CertificateConstants.X_509_CERTIFICATE;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.StringWriter;
+import java.security.Security;
+import java.security.cert.Certificate;
+import java.security.cert.CertificateFactory;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+import org.bouncycastle.jce.provider.BouncyCastleProvider;
+import org.bouncycastle.openssl.jcajce.JcaMiscPEMGenerator;
+import org.bouncycastle.util.io.pem.PemObjectGenerator;
+import org.bouncycastle.util.io.pem.PemWriter;
+import org.onap.oom.certservice.postprocessor.merger.exception.MissingTruststoreException;
+import org.onap.oom.certservice.postprocessor.merger.exception.TruststoreDataOperationException;
+import org.onap.oom.certservice.postprocessor.merger.exception.WriteTruststoreFileException;
+import org.onap.oom.certservice.postprocessor.common.FileTools;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAlias;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAliasFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class PemTruststore extends Truststore {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PemTruststore.class);
+
+    private static final boolean APPEND_TO_FILE = true;
+
+    private final CertificateWithAliasFactory factory = new CertificateWithAliasFactory();
+    private final List<CertificateWithAlias> certificatesToBeSaved = new ArrayList<>();
+
+    public PemTruststore(File storeFile) {
+        super(storeFile, new FileTools());
+    }
+
+    public List<CertificateWithAlias> getCertificates()
+        throws TruststoreDataOperationException, MissingTruststoreException {
+        LOGGER.debug("Attempt to read certificates from file: {}", storeFile.getPath());
+        if (isFileWithoutPemCertificate()) {
+            throw new MissingTruststoreException("File does not contain any certificate");
+        }
+        List<Certificate> extractedCertificate = extractCertificatesFromFile();
+        return wrapCertificates(extractedCertificate);
+    }
+
+    public void addCertificates(List<CertificateWithAlias> certificates)
+        throws TruststoreDataOperationException, MissingTruststoreException {
+        LOGGER.debug("Attempt to add certificates for saving to file");
+        if (isFileWithoutPemCertificate()) {
+            LOGGER.error("File does not contain any certificate. File path: {} ", storeFile.getPath());
+            throw new MissingTruststoreException("File does not contain any certificate");
+        }
+        certificatesToBeSaved.addAll(certificates);
+    }
+
+    public void saveFile() throws WriteTruststoreFileException, TruststoreDataOperationException {
+        LOGGER.debug("Attempt to save file: {}", storeFile.getPath());
+        List<Certificate> certificates = certificatesToBeSaved.stream()
+            .map(CertificateWithAlias::getCertificate)
+            .collect(Collectors.toList());
+        String certificatesAsString = transformToStringInPemFormat(certificates);
+        appendToFile(certificatesAsString);
+    }
+
+    boolean isFileWithoutPemCertificate() throws TruststoreDataOperationException {
+        List<Certificate> certificateList = extractCertificatesFromFile();
+        return certificateList.isEmpty();
+    }
+
+    String transformToStringInPemFormat(List<Certificate> certificates) throws TruststoreDataOperationException {
+        StringWriter sw = new StringWriter();
+        List<PemObjectGenerator> generators = transformToPemGenerators(certificates);
+        try (PemWriter pemWriter = new PemWriter(sw)) {
+            for (PemObjectGenerator generator : generators) {
+                pemWriter.writeObject(generator);
+            }
+        } catch (IOException e) {
+            LOGGER.error("Cannot convert certificates to PEM format");
+            throw new TruststoreDataOperationException(e);
+        }
+        return sw.toString();
+    }
+
+    private List<Certificate> extractCertificatesFromFile() throws TruststoreDataOperationException {
+        try (FileInputStream inputStream = new FileInputStream(storeFile)) {
+            Security.addProvider(new BouncyCastleProvider());
+            CertificateFactory factory = CertificateFactory.getInstance(X_509_CERTIFICATE, BOUNCY_CASTLE_PROVIDER);
+            return new ArrayList<>(factory.generateCertificates(inputStream));
+        } catch (Exception e) {
+            LOGGER.error("Cannot read certificates from file: {}", storeFile.getPath());
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private List<PemObjectGenerator> transformToPemGenerators(List<Certificate> certificates)
+        throws TruststoreDataOperationException {
+        List<PemObjectGenerator> generators = new ArrayList<>();
+        for (Certificate certificate : certificates) {
+            PemObjectGenerator generator = createPemGenerator(certificate);
+            generators.add(generator);
+        }
+        return generators;
+    }
+
+    private JcaMiscPEMGenerator createPemGenerator(Certificate certificate)
+        throws TruststoreDataOperationException {
+        try {
+            return new JcaMiscPEMGenerator(certificate);
+        } catch (IOException e) {
+            LOGGER.error("Cannot convert Certificate Object to PemGenerator Object");
+            throw new TruststoreDataOperationException(e);
+        }
+    }
+
+    private List<CertificateWithAlias> wrapCertificates(List<Certificate> rawCertificates) {
+        return rawCertificates.stream()
+            .map(factory::createPemCertificate)
+            .collect(Collectors.toList());
+    }
+
+    private void appendToFile(String certificatesAsString) throws WriteTruststoreFileException {
+        try {
+            FileOutputStream fileOutputStream = new FileOutputStream(storeFile, APPEND_TO_FILE);
+            fileOutputStream.write(certificatesAsString.getBytes());
+        } catch (Exception e) {
+            LOGGER.error("Cannot write certificates to file");
+            throw new WriteTruststoreFileException(e);
+        }
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/Truststore.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/Truststore.java
new file mode 100644
index 00000000..058613a9
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/Truststore.java
@@ -0,0 +1,47 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model;
+
+import java.io.File;
+import java.util.List;
+import org.onap.oom.certservice.postprocessor.common.FileTools;
+import org.onap.oom.certservice.postprocessor.merger.model.certificate.CertificateWithAlias;
+
+public abstract class Truststore {
+
+    final File storeFile;
+
+    private final FileTools fileTools;
+
+    public Truststore(File storeFile, FileTools fileTools) {
+        this.storeFile = storeFile;
+        this.fileTools = fileTools;
+    }
+
+    public void createBackup() {
+        fileTools.createBackup(storeFile);
+    }
+
+    public abstract List<CertificateWithAlias> getCertificates();
+
+    public abstract void addCertificates(List<CertificateWithAlias> certificates);
+
+    public abstract void saveFile();
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/TruststoreFactory.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/TruststoreFactory.java
new file mode 100644
index 00000000..5167c301
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/TruststoreFactory.java
@@ -0,0 +1,64 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model;
+
+import static org.onap.oom.certservice.postprocessor.api.CertificateConstants.JKS_TYPE;
+import static org.onap.oom.certservice.postprocessor.api.CertificateConstants.PKCS12_TYPE;
+
+import java.io.File;
+import org.onap.oom.certservice.postprocessor.common.ExtensionResolver;
+import org.onap.oom.certservice.postprocessor.merger.exception.TruststoreFileFactoryException;
+
+public class TruststoreFactory {
+
+    private static final String JKS_EXTENSION = ".jks";
+    private static final String P12_EXTENSION = ".p12";
+    private static final String PEM_EXTENSION = ".pem";
+    private static final String FILE_DOES_NOT_EXIST_MSG_TEMPLATE = "File: %s does not exist";
+    private static final String UNKNOWN_TRUSTSTORE_TYPE_MSG_TEMPLATE = "Unknown truststore extension type: %s";
+
+
+    private TruststoreFactory() {
+    }
+
+    public static Truststore create(String truststoreFilePath, String truststorePasswordPath) {
+        File truststoreFile = new File(truststoreFilePath);
+        if (!ExtensionResolver.checkIfFileExists(truststoreFile)) {
+            throw new TruststoreFileFactoryException(String.format(FILE_DOES_NOT_EXIST_MSG_TEMPLATE, truststoreFile));
+        }
+        return createTypedTruststore(truststoreFile, truststorePasswordPath);
+    }
+
+    private static Truststore createTypedTruststore(File truststoreFile, String truststorePasswordPath) {
+        String extension = ExtensionResolver.get(truststoreFile);
+        switch (extension) {
+            case JKS_EXTENSION:
+                return JavaTruststoreFactory.create(truststoreFile, truststorePasswordPath, JKS_TYPE);
+            case P12_EXTENSION:
+                return JavaTruststoreFactory.create(truststoreFile, truststorePasswordPath, PKCS12_TYPE);
+            case PEM_EXTENSION:
+                return new PemTruststore(truststoreFile);
+            default:
+                throw new TruststoreFileFactoryException(
+                    String.format(UNKNOWN_TRUSTSTORE_TYPE_MSG_TEMPLATE, extension));
+        }
+    }
+
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAlias.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAlias.java
new file mode 100644
index 00000000..098ffcd0
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAlias.java
@@ -0,0 +1,41 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model.certificate;
+
+import java.security.cert.Certificate;
+
+public class CertificateWithAlias {
+
+    private final Certificate certificate;
+    private final String alias;
+
+    public CertificateWithAlias(Certificate certificate, String alias) {
+        this.certificate = certificate;
+        this.alias = alias;
+    }
+
+    public String getAlias() {
+        return this.alias;
+    }
+
+    public Certificate getCertificate() {
+        return this.certificate;
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAliasFactory.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAliasFactory.java
new file mode 100644
index 00000000..4ad2b417
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/CertificateWithAliasFactory.java
@@ -0,0 +1,33 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model.certificate;
+
+import java.security.cert.Certificate;
+
+public class CertificateWithAliasFactory {
+
+    public CertificateWithAlias createCertificateWithAlias(Certificate certificate, String alias) {
+        return new CertificateWithAlias(certificate, alias);
+    }
+
+    public CertificateWithAlias createPemCertificate(Certificate certificate) {
+        return new CertificateWithAlias(certificate, PemAliasGenerator.getInstance().getAlias());
+    }
+}
diff --git a/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/PemAliasGenerator.java b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/PemAliasGenerator.java
new file mode 100644
index 00000000..a89b1031
--- /dev/null
+++ b/certServicePostProcessor/src/main/java/org/onap/oom/certservice/postprocessor/merger/model/certificate/PemAliasGenerator.java
@@ -0,0 +1,42 @@
+/*============LICENSE_START=======================================================
+ * oom-truststore-merger
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.oom.certservice.postprocessor.merger.model.certificate;
+
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class PemAliasGenerator {
+
+    private static final String PREFIX_ALIAS_NAME = "pem-trusted-certificate-";
+    private static final PemAliasGenerator INSTANCE = new PemAliasGenerator();
+    private static AtomicInteger counter = new AtomicInteger(0);
+
+    private PemAliasGenerator() {
+    }
+
+    public static PemAliasGenerator getInstance() {
+        return INSTANCE;
+    }
+
+    public String getAlias() {
+
+        return PREFIX_ALIAS_NAME + counter.getAndIncrement();
+    }
+}
diff --git a/certServicePostProcessor/src/main/resources/log4j2.xml b/certServicePostProcessor/src/main/resources/log4j2.xml
new file mode 100644
index 00000000..697017e3
--- /dev/null
+++ b/certServicePostProcessor/src/main/resources/log4j2.xml
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<Configuration status="INFO">
+
+    <Appenders>
+        <Console name="CONSOLE" target="SYSTEM_OUT">
+            <PatternLayout
+                    pattern="%d{${LOG_DATEFORMAT_PATTERN:-yyyy-MM-dd HH:mm:ss.SSS}} %highlight{${LOG_LEVEL_PATTERN:-%5p}}{FATAL=red blink, ERROR=red, WARN=yellow bold, INFO=green, DEBUG=green bold, TRACE=blue} %style{%pid}{magenta} [%15.15t] %style{%-40.40C{1.}}{cyan} : %m%n%throwable"/>
+        </Console>
+
+        <RollingFile fileName="var/log/onap/oom/truststore-merger/truststore-merger.log"
+                     filePattern="logs/truststore-merger-%d{yyyy-MM-dd}-%i.log" name="ROLLING_FILE">
+            <PatternLayout pattern="[%d{ISO8601}][%-5p][%-5c] %m%n"/>
+            <Policies>
+                <SizeBasedTriggeringPolicy size="64 MB"/>
+            </Policies>
+            <DefaultRolloverStrategy max="10"/>
+        </RollingFile>
+
+    </Appenders>
+
+    <Loggers>
+
+        <Root level="DEBUG">
+            <AppenderRef ref="CONSOLE"/>
+            <AppenderRef ref="ROLLING_FILE"/>
+        </Root>
+
+    </Loggers>
+</Configuration>