[OOM-CPMv2] Allow optional input parameters

Bug fix in merger to allow KEYSTORE paths to be optional.

Issue-ID: DCAEGEN2-2253
Signed-off-by: kjaniak <kornel.janiak@nokia.com>
Change-Id: I9176d7fdb0e714d849a4ea617ccc4f8eb6a233e1

18 files changed, 414 insertions, 478 deletions

diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/api/ExitStatus.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/api/ExitStatus.java
index 01f440cc..2c3945c5 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/api/ExitStatus.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/api/ExitStatus.java
@@ -22,8 +22,8 @@ package org.onap.oom.truststoremerger.api;
 public enum ExitStatus {
 
     SUCCESS(0, "Success"),
-    TRUSTSTORES_PATHS_PROVIDER_EXCEPTION(1, "Invalid paths in environment variables"),
-    MERGER_CONFIGURATION_EXCEPTION(2, "Invalid merger configuration"),
+    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"),
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationLoader.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationLoader.java
index 7660ff7b..0f538e1d 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationLoader.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationLoader.java
@@ -21,22 +21,14 @@ package org.onap.oom.truststoremerger.configuration;
 
 import org.onap.oom.truststoremerger.api.ExitableException;
 import org.onap.oom.truststoremerger.configuration.model.AppConfiguration;
-import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsReader;
-import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsReaderFactory;
-import org.onap.oom.truststoremerger.configuration.path.env.EnvProvider;
+import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsSplitter;
+import org.onap.oom.truststoremerger.configuration.path.env.EnvReader;
 
 public class AppConfigurationLoader {
 
     public AppConfiguration loadConfiguration() throws ExitableException {
-        DelimitedPathsReaderFactory readerFactory = new DelimitedPathsReaderFactory(new EnvProvider());
-        DelimitedPathsReader certificatesPathsReader = readerFactory.createCertificatePathsReader();
-        DelimitedPathsReader passwordsPathsReader = readerFactory.createPasswordPathsReader();
-        DelimitedPathsReader copierPathsReader = readerFactory.createKeystoreCopierPathsReader();
-        AppConfigurationProvider factory = new AppConfigurationProvider(certificatesPathsReader,
-            passwordsPathsReader,
-            copierPathsReader);
+        DelimitedPathsSplitter pathsSplitter = new DelimitedPathsSplitter();
+        AppConfigurationProvider factory = new AppConfigurationProvider(pathsSplitter, new EnvReader());
         return factory.createConfiguration();
     }
-
-
 }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProvider.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProvider.java
index e1bdbfa3..33ea8e4b 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProvider.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProvider.java
@@ -19,51 +19,65 @@
 
 package org.onap.oom.truststoremerger.configuration;
 
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.KEYSTORE_DESTINATION_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.KEYSTORE_SOURCE_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PASSWORDS_PATHS_ENV;
 
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.KEYSTORE_DESTINATION_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.KEYSTORE_SOURCE_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PASSWORDS_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PATHS_ENV;
+
+import java.util.Collections;
 import java.util.List;
-import org.onap.oom.truststoremerger.configuration.exception.MergerConfigurationException;
-import org.onap.oom.truststoremerger.configuration.exception.TruststoresPathsProviderException;
+import java.util.Optional;
+import org.onap.oom.truststoremerger.configuration.exception.CertificatesPathsValidationException;
+import org.onap.oom.truststoremerger.configuration.exception.ConfigurationException;
 import org.onap.oom.truststoremerger.configuration.model.AppConfiguration;
-import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsReader;
+import org.onap.oom.truststoremerger.configuration.model.EnvVariable;
+import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsSplitter;
+import org.onap.oom.truststoremerger.configuration.path.env.EnvReader;
 
 public class AppConfigurationProvider {
 
-    private final DelimitedPathsReader truststoresPathsReader;
-    private final DelimitedPathsReader truststoresPasswordsPathsReader;
-    private final DelimitedPathsReader copierPathsReader;
+    private final EnvReader envReader;
+    private final DelimitedPathsSplitter pathsSplitter;
 
-    public AppConfigurationProvider(DelimitedPathsReader truststoresPathsReader,
-        DelimitedPathsReader truststoresPasswordsPathsReader, DelimitedPathsReader copierPathsReader) {
-        this.truststoresPathsReader = truststoresPathsReader;
-        this.truststoresPasswordsPathsReader = truststoresPasswordsPathsReader;
-        this.copierPathsReader = copierPathsReader;
+    public AppConfigurationProvider(DelimitedPathsSplitter pathsSplitter, EnvReader envReader) {
+        this.envReader = envReader;
+        this.pathsSplitter = pathsSplitter;
     }
 
     public AppConfiguration createConfiguration()
-        throws MergerConfigurationException, TruststoresPathsProviderException {
-        List<String> truststoresPaths = truststoresPathsReader.get(TRUSTSTORES_PATHS_ENV);
-        List<String> truststoresPasswordsPaths = truststoresPasswordsPathsReader.get(TRUSTSTORES_PASSWORDS_PATHS_ENV);
-        List<String> sourceKeystorePaths = copierPathsReader.get(KEYSTORE_SOURCE_PATHS_ENV);
-        List<String> destinationKeystorePaths = copierPathsReader.get(KEYSTORE_DESTINATION_PATHS_ENV);
+        throws ConfigurationException, CertificatesPathsValidationException {
+
+        List<String> truststoresPaths = getPaths(TRUSTSTORES_PATHS_ENV);
+        List<String> truststoresPasswordsPaths = getPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV);
+        List<String> sourceKeystorePaths = getPaths(KEYSTORE_SOURCE_PATHS_ENV);
+        List<String> destinationKeystorePaths = getPaths(KEYSTORE_DESTINATION_PATHS_ENV);
 
-        ensureSameSize(truststoresPaths, truststoresPasswordsPaths, TRUSTSTORES_PATHS_ENV,
-            TRUSTSTORES_PASSWORDS_PATHS_ENV);
-        ensureSameSize(sourceKeystorePaths, destinationKeystorePaths, KEYSTORE_SOURCE_PATHS_ENV,
-            KEYSTORE_DESTINATION_PATHS_ENV);
+        ensureSameSize(truststoresPaths, truststoresPasswordsPaths, TRUSTSTORES_PATHS_ENV.name(),
+            TRUSTSTORES_PASSWORDS_PATHS_ENV.name());
+        ensureSameSize(sourceKeystorePaths, destinationKeystorePaths, KEYSTORE_SOURCE_PATHS_ENV.name(),
+            KEYSTORE_DESTINATION_PATHS_ENV.name());
 
         return new AppConfiguration(truststoresPaths, truststoresPasswordsPaths, sourceKeystorePaths,
             destinationKeystorePaths);
     }
 
+    private List<String> getPaths(EnvVariable envVariable) throws ConfigurationException {
+        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)
-        throws MergerConfigurationException {
+        String secondListEnvName) throws ConfigurationException {
         if (firstList.size() != secondList.size()) {
-            throw new MergerConfigurationException(
+            throw new ConfigurationException(
                 "Size of " + firstListEnvName
                     + " does not match size of " + secondListEnvName + " environment variables");
         }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/ConfigurationEnvs.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/ConfigurationEnvs.java
deleted file mode 100644
index fa72e4b0..00000000
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/ConfigurationEnvs.java
+++ /dev/null
@@ -1,33 +0,0 @@
-/*============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.truststoremerger.configuration;
-
-public final class ConfigurationEnvs {
-
-    private ConfigurationEnvs() {
-
-    }
-
-    public static final String TRUSTSTORES_PATHS_ENV = "TRUSTSTORES_PATHS";
-    public static final String TRUSTSTORES_PASSWORDS_PATHS_ENV = "TRUSTSTORES_PASSWORDS_PATHS";
-    public static final String KEYSTORE_SOURCE_PATHS_ENV = "KEYSTORE_SOURCE_PATHS";
-    public static final String KEYSTORE_DESTINATION_PATHS_ENV = "KEYSTORE_DESTINATION_PATHS";
-
-}
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/TruststoresPathsProviderException.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/CertificatesPathsValidationException.java
index 6089d314..1069a0fe 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/TruststoresPathsProviderException.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/CertificatesPathsValidationException.java
@@ -22,9 +22,9 @@ package org.onap.oom.truststoremerger.configuration.exception;
 import org.onap.oom.truststoremerger.api.ExitStatus;
 import org.onap.oom.truststoremerger.api.ExitableException;
 
-public class TruststoresPathsProviderException extends ExitableException {
+public class CertificatesPathsValidationException extends ExitableException {
 
-    public TruststoresPathsProviderException(String errorMessage) {
-        super(errorMessage, ExitStatus.TRUSTSTORES_PATHS_PROVIDER_EXCEPTION);
+    public CertificatesPathsValidationException(String errorMessage) {
+        super(errorMessage, ExitStatus.CERTIFICATES_PATHS_VALIDATION_EXCEPTION);
     }
 }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/MergerConfigurationException.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/ConfigurationException.java
index 4bdfd9f4..ffb99dae 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/MergerConfigurationException.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/exception/ConfigurationException.java
@@ -22,9 +22,9 @@ package org.onap.oom.truststoremerger.configuration.exception;
 import org.onap.oom.truststoremerger.api.ExitStatus;
 import org.onap.oom.truststoremerger.api.ExitableException;
 
-public class MergerConfigurationException extends ExitableException {
+public class ConfigurationException extends ExitableException {
 
-    public MergerConfigurationException(String errorMessage) {
-        super(errorMessage, ExitStatus.MERGER_CONFIGURATION_EXCEPTION);
+    public ConfigurationException(String errorMessage) {
+        super(errorMessage, ExitStatus.CONFIGURATION_EXCEPTION);
     }
 }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderFactory.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/model/EnvVariable.java
index b2a64f97..456c58f8 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderFactory.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/model/EnvVariable.java
@@ -17,30 +17,35 @@
  * ============LICENSE_END=========================================================
  */
 
-package org.onap.oom.truststoremerger.configuration.path;
+package org.onap.oom.truststoremerger.configuration.model;
 
 import static org.onap.oom.truststoremerger.configuration.path.validation.ValidationFunctions.doesItContainValidCertificatesPaths;
 import static org.onap.oom.truststoremerger.configuration.path.validation.ValidationFunctions.doesItContainValidPasswordPaths;
 import static org.onap.oom.truststoremerger.configuration.path.validation.ValidationFunctions.doesItContainValidPathsToCopy;
 
-import org.onap.oom.truststoremerger.configuration.path.env.EnvProvider;
+import java.util.List;
+import java.util.function.Predicate;
 
-public final class DelimitedPathsReaderFactory {
-    private final EnvProvider envProvider;
+public enum EnvVariable {
+    TRUSTSTORES_PATHS_ENV(true, doesItContainValidCertificatesPaths()),
+    TRUSTSTORES_PASSWORDS_PATHS_ENV(true, doesItContainValidPasswordPaths()),
+    KEYSTORE_SOURCE_PATHS_ENV(false, doesItContainValidPathsToCopy()),
+    KEYSTORE_DESTINATION_PATHS_ENV(false, doesItContainValidPathsToCopy());
 
-    public DelimitedPathsReaderFactory(EnvProvider envProvider) {
-        this.envProvider = envProvider;
-    }
+    boolean isMandatory;
+
+    Predicate<List<String>> validationFunction;
 
-    public DelimitedPathsReader createPasswordPathsReader() {
-        return new DelimitedPathsReader(envProvider, doesItContainValidPasswordPaths());
+    EnvVariable(boolean isMandatory, Predicate<List<String>> validationFunction) {
+        this.isMandatory = isMandatory;
+        this.validationFunction = validationFunction;
     }
 
-    public DelimitedPathsReader createCertificatePathsReader() {
-        return new DelimitedPathsReader(envProvider, doesItContainValidCertificatesPaths());
+    public boolean isMandatory() {
+        return isMandatory;
     }
 
-    public DelimitedPathsReader createKeystoreCopierPathsReader() {
-        return new DelimitedPathsReader(envProvider, doesItContainValidPathsToCopy());
+    public Predicate<List<String>> getValidationFunction() {
+        return validationFunction;
     }
 }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReader.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsSplitter.java
index e5de4d08..b7a4f4c5 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReader.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsSplitter.java
@@ -21,30 +21,22 @@ package org.onap.oom.truststoremerger.configuration.path;
 
 import java.util.Arrays;
 import java.util.List;
-import java.util.function.Predicate;
-import org.onap.oom.truststoremerger.configuration.exception.TruststoresPathsProviderException;
-import org.onap.oom.truststoremerger.configuration.path.env.EnvProvider;
+import java.util.Optional;
+import org.onap.oom.truststoremerger.configuration.exception.CertificatesPathsValidationException;
+import org.onap.oom.truststoremerger.configuration.model.EnvVariable;
 
-public class DelimitedPathsReader {
+public class DelimitedPathsSplitter {
 
     private static final String DELIMITER = ":";
     private static final int NEGATIVE_SPLIT_LIMIT = -1;
 
-    private final EnvProvider envProvider;
-    private final Predicate<List<String>> pathsValidator;
-
-    DelimitedPathsReader(EnvProvider envProvider, Predicate<List<String>> pathsValidator) {
-        this.envProvider = envProvider;
-        this.pathsValidator = pathsValidator;
-    }
-
-    public List<String> get(String envName) throws TruststoresPathsProviderException {
-        return envProvider.getEnv(envName)
-            .filter(this::hasValue)
+    public List<String> getValidatedPaths(EnvVariable envVariable, Optional<String> envValue)
+        throws CertificatesPathsValidationException {
+        return envValue.filter(this::hasValue)
             .map(this::splitToList)
-            .filter(pathsValidator)
-            .orElseThrow(() -> new TruststoresPathsProviderException(
-                envName + " environment variable does not contain valid paths"));
+            .filter(envVariable.getValidationFunction())
+            .orElseThrow(() -> new CertificatesPathsValidationException(
+                envVariable + " environment variable does not contain valid paths"));
     }
 
     private boolean hasValue(String envValue) {
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/env/EnvProvider.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/env/EnvReader.java
index 1dd127d0..cb6099c1 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/env/EnvProvider.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/env/EnvReader.java
@@ -20,17 +20,20 @@
 package org.onap.oom.truststoremerger.configuration.path.env;
 
 import java.util.Optional;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-public class EnvProvider {
+public class EnvReader {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(EnvProvider.class);
+    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(System.getenv(name));
+        return Optional.ofNullable(value);
     }
 }
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/validation/ValidationFunctions.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/validation/ValidationFunctions.java
index f4cfa60c..535d2e6e 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/validation/ValidationFunctions.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/configuration/path/validation/ValidationFunctions.java
@@ -25,7 +25,7 @@ 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 TRUSTSTORE_PASSWORD_PATH_REGEX = "^(/[a-zA-Z0-9_-]+)+\\.pass";
+    private static final String CERTIFICATE_PASSWORD_PATH_REGEX = "^(/[a-zA-Z0-9_-]+)+\\.pass";
 
     private ValidationFunctions() {
     }
@@ -40,7 +40,7 @@ public final class ValidationFunctions {
 
     public static Predicate<List<String>> doesItContainValidPathsToCopy() {
         return paths -> paths.stream().allMatch(path ->
-            doesMatch(path, TRUSTSTORE_PASSWORD_PATH_REGEX) || isCertificatePathValid(path));
+            doesMatch(path, CERTIFICATE_PASSWORD_PATH_REGEX) || isCertificatePathValid(path));
     }
 
     private static boolean isCertificatePathValid(String path) {
@@ -48,7 +48,7 @@ public final class ValidationFunctions {
     }
 
     private static boolean isCertificatePasswordPathValid(String path) {
-        return path.isEmpty() || doesMatch(path, TRUSTSTORE_PASSWORD_PATH_REGEX);
+        return path.isEmpty() || doesMatch(path, CERTIFICATE_PASSWORD_PATH_REGEX);
     }
 
     private static boolean doesMatch(String path, String regex) {
diff --git a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/copier/KeystoreCopier.java b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/copier/KeystoreCopier.java
index 822979c1..7678397a 100644
--- a/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/copier/KeystoreCopier.java
+++ b/trustStoreMerger/src/main/java/org/onap/oom/truststoremerger/copier/KeystoreCopier.java
@@ -26,20 +26,23 @@ import org.onap.oom.truststoremerger.common.FileTools;
 import org.onap.oom.truststoremerger.configuration.model.AppConfiguration;
 import org.onap.oom.truststoremerger.copier.exception.KeystoreFileCopyException;
 import org.onap.oom.truststoremerger.copier.exception.KeystoreNotExistException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class KeystoreCopier {
 
-    final private FileTools fileTools;
+    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 {
-            final List<String> sources = configuration.getSourceKeystorePaths();
-            final List<String> destinations = configuration.getDestinationKeystorePaths();
-
             for (int i = 0; i < sources.size(); i++) {
                 copy(sources.get(i), destinations.get(i));
             }
@@ -48,6 +51,12 @@ public class KeystoreCopier {
         }
     }
 
+    private void containsPaths(List<String> sources) {
+        if (sources.size() == 0) {
+            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);
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/common/ExtensionResolverTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/common/ExtensionResolverTest.java
index e59a7671..0ed17d0c 100644
--- a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/common/ExtensionResolverTest.java
+++ b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/common/ExtensionResolverTest.java
@@ -17,7 +17,6 @@
  * ============LICENSE_END=========================================================
  */
 
-
 package org.onap.oom.truststoremerger.common;
 
 import org.junit.jupiter.params.ParameterizedTest;
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProviderTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProviderTest.java
new file mode 100644
index 00000000..a8da405d
--- /dev/null
+++ b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/AppConfigurationProviderTest.java
@@ -0,0 +1,141 @@
+/*============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.truststoremerger.configuration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+import static org.mockito.Mockito.when;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.KEYSTORE_DESTINATION_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.KEYSTORE_SOURCE_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PASSWORDS_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PATHS_ENV;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.onap.oom.truststoremerger.configuration.exception.CertificatesPathsValidationException;
+import org.onap.oom.truststoremerger.configuration.exception.ConfigurationException;
+import org.onap.oom.truststoremerger.configuration.model.AppConfiguration;
+import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsSplitter;
+import org.onap.oom.truststoremerger.configuration.path.env.EnvReader;
+
+@ExtendWith(MockitoExtension.class)
+class AppConfigurationProviderTest {
+
+    private static final String BASE_TRUSTSTORE_PATH = "/opt/app/truststore_";
+    private static final String JKS_EXTENSION = ".jks";
+    private static final String PASS_EXTENSION = ".pass";
+    private static final String TRUSTSTORES_PATHS = "/opt/app/certificates/truststore.jks:/opt/app/certificates/truststore.pem";
+    private static final String TRUSTSTORES_PASSWORDS_PATHS = "/opt/app/certificates/truststore.pass:/trust.pass";
+
+    @Mock
+    private DelimitedPathsSplitter pathsSplitter;
+    @Mock
+    private EnvReader envReader;
+    private AppConfigurationProvider provider;
+
+    @BeforeEach
+    void setUp() {
+        provider = new AppConfigurationProvider(pathsSplitter, envReader);
+    }
+
+    @Test
+    void shouldThrowExceptionWhenMandatoryEnvNotPresent() {
+        // given
+        when(envReader.getEnv(TRUSTSTORES_PATHS_ENV.name())).thenReturn(Optional.empty());
+        // when, then
+        assertThatExceptionOfType(ConfigurationException.class).isThrownBy(() -> provider.createConfiguration())
+            .withMessageContaining(TRUSTSTORES_PATHS_ENV + " mandatory environment variable is not defined");
+    }
+
+    @Test
+    void shouldThrowExceptionWhenTrustorePathsSizesDoNotMatch() {
+        // given
+        List<String> truststores = createListOfPathsWithExtension(2, JKS_EXTENSION);
+        List<String> truststoresPasswords = createListOfPathsWithExtension(1, PASS_EXTENSION);
+
+        mockTruststorePaths(truststores, truststoresPasswords);
+        // when
+        assertThatExceptionOfType(ConfigurationException.class)
+            .isThrownBy(() -> provider.createConfiguration())
+            .withMessageContaining("Size of " + TRUSTSTORES_PATHS_ENV
+                + " does not match size of " + TRUSTSTORES_PASSWORDS_PATHS_ENV + " environment variables");
+    }
+
+    @Test
+    void shouldReturnEmptyListWhenOptionalEnvNotPresent() {
+        // given
+        List<String> truststores = createListOfPathsWithExtension(2, JKS_EXTENSION);
+        List<String> truststoresPasswords = createListOfPathsWithExtension(2, PASS_EXTENSION);
+        mockTruststorePaths(truststores, truststoresPasswords);
+        mockKeystorePaths(Optional.empty(), Optional.empty());
+        // when
+        AppConfiguration paths = provider.createConfiguration();
+        // then
+        assertThat(paths.getDestinationKeystorePaths()).isEmpty();
+        assertThat(paths.getSourceKeystorePaths()).isEmpty();
+    }
+
+    private void mockTruststorePaths(List<String> truststores, List<String> truststoresPasswords) {
+        mockTruststores(truststores);
+        mockTruststoresPasswords(truststoresPasswords);
+    }
+
+    private void mockKeystorePaths(Optional<String> sourceKeystoresPairPaths, Optional<String> destKeystoresPairPaths) {
+        mockKeystoreCopierSourcePaths(sourceKeystoresPairPaths);
+        mockKeystoreCopierDestinationPaths(destKeystoresPairPaths);
+    }
+
+    private void mockTruststores(List<String> truststores) throws CertificatesPathsValidationException {
+        when(envReader.getEnv(TRUSTSTORES_PATHS_ENV.name())).thenReturn(Optional.of(TRUSTSTORES_PATHS));
+        when(pathsSplitter.getValidatedPaths(TRUSTSTORES_PATHS_ENV, Optional.of(TRUSTSTORES_PATHS)))
+            .thenReturn(truststores);
+    }
+
+    private void mockTruststoresPasswords(List<String> truststoresPasswords)
+        throws CertificatesPathsValidationException {
+        Optional<String> passwordsPaths = Optional.of(TRUSTSTORES_PASSWORDS_PATHS);
+        when(envReader.getEnv(TRUSTSTORES_PASSWORDS_PATHS_ENV.name())).thenReturn(passwordsPaths);
+        when(pathsSplitter.getValidatedPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV, passwordsPaths))
+            .thenReturn(truststoresPasswords);
+    }
+
+    private void mockKeystoreCopierSourcePaths(Optional<String> paths) {
+        when(envReader.getEnv(KEYSTORE_SOURCE_PATHS_ENV.name())).thenReturn(paths);
+    }
+
+    private void mockKeystoreCopierDestinationPaths(Optional<String> paths) {
+        when(envReader.getEnv(KEYSTORE_DESTINATION_PATHS_ENV.name())).thenReturn(paths);
+    }
+
+    private List<String> createListOfPathsWithExtension(int numberOfPaths, String passwordExtension) {
+        List<String> paths = new ArrayList<>();
+        while (numberOfPaths-- > 0) {
+            paths.add(BASE_TRUSTSTORE_PATH + numberOfPaths + passwordExtension);
+        }
+        return paths;
+    }
+
+}
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/MergerConfigurationProviderTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/MergerConfigurationProviderTest.java
deleted file mode 100644
index 026199f4..00000000
--- a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/MergerConfigurationProviderTest.java
+++ /dev/null
@@ -1,172 +0,0 @@
-/*============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.truststoremerger.configuration;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.mockito.Mockito.when;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.KEYSTORE_DESTINATION_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.KEYSTORE_SOURCE_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PASSWORDS_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PATHS_ENV;
-
-import java.util.ArrayList;
-import java.util.List;
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.extension.ExtendWith;
-import org.mockito.Mock;
-import org.mockito.junit.jupiter.MockitoExtension;
-import org.onap.oom.truststoremerger.configuration.exception.MergerConfigurationException;
-import org.onap.oom.truststoremerger.configuration.exception.TruststoresPathsProviderException;
-import org.onap.oom.truststoremerger.configuration.model.AppConfiguration;
-import org.onap.oom.truststoremerger.configuration.path.DelimitedPathsReader;
-
-@ExtendWith(MockitoExtension.class)
-class MergerConfigurationProviderTest {
-
-    private static final String BASE_TRUSTSTORE_PATH = "/opt/app/truststore_";
-    private static final String KEYSTORE_PATH = "/opt/app/keystore_";
-    private static final String ANOTHER_KEYSTORE_PATH = "/opt/app/external/keystore_";
-    private static final String JKS_EXTENSION = ".jks";
-    private static final String PEM_EXTENSION = ".pem";
-    private static final String PASS_EXTENSION = ".pass";
-
-    @Mock
-    private DelimitedPathsReader certificatesPathsProvider;
-    @Mock
-    private DelimitedPathsReader passwordsPathsProvider;
-    @Mock
-    private DelimitedPathsReader copierPathsReader;
-    private AppConfigurationProvider factory;
-
-    @BeforeEach
-    void setUp() {
-        factory = new AppConfigurationProvider(certificatesPathsProvider, passwordsPathsProvider, copierPathsReader);
-    }
-
-    @Test
-    void shouldReturnConfigurationWithCorrectPaths()
-        throws TruststoresPathsProviderException, MergerConfigurationException {
-        int numberOfPaths = 5;
-        List<String> truststoresPaths = createListOfPathsWithExtension(numberOfPaths, JKS_EXTENSION);
-        List<String> truststorePasswordPaths = createListOfPathsWithExtension(numberOfPaths, PASS_EXTENSION);
-        mockTruststorePaths(truststoresPaths, truststorePasswordPaths);
-
-        List<String> sourceKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(KEYSTORE_PATH,
-            numberOfPaths, PEM_EXTENSION);
-        List<String> destKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(ANOTHER_KEYSTORE_PATH,
-            numberOfPaths, PEM_EXTENSION);
-        mockKeystorePaths(sourceKeystoresPairPaths, destKeystoresPairPaths);
-
-        AppConfiguration configuration = factory.createConfiguration();
-
-        assertThat(configuration.getTruststoreFilePaths()).containsAll(truststoresPaths);
-        assertThat(configuration.getTruststoreFilePasswordPaths()).containsAll(truststorePasswordPaths);
-        assertThat(configuration.getSourceKeystorePaths()).containsAll(sourceKeystoresPairPaths);
-        assertThat(configuration.getDestinationKeystorePaths()).containsAll(destKeystoresPairPaths);
-    }
-
-    @Test
-    void shouldThrowExceptionWhenTruststoresLengthDifferentThanTruststoresPasswordsLength()
-        throws TruststoresPathsProviderException {
-        int numberOfCertificates = 5;
-        int numberOfTruststoresPasswords = 4;
-        List<String> truststoresPaths = createListOfPathsWithExtension(numberOfCertificates, JKS_EXTENSION);
-        List<String> truststorePasswordPaths = createListOfPathsWithExtension(numberOfTruststoresPasswords, PASS_EXTENSION);
-        mockTruststorePaths(truststoresPaths, truststorePasswordPaths);
-
-        List<String> sourceKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(KEYSTORE_PATH,
-            numberOfCertificates, PEM_EXTENSION);
-        List<String> destKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(ANOTHER_KEYSTORE_PATH,
-            numberOfCertificates, PEM_EXTENSION);
-        mockKeystorePaths(sourceKeystoresPairPaths, destKeystoresPairPaths);
-
-        assertThatExceptionOfType(MergerConfigurationException.class)
-            .isThrownBy(factory::createConfiguration);
-    }
-
-    @Test
-    void shouldThrowExceptionWhenSourceLengthDifferentThanDestinationLength()
-        throws TruststoresPathsProviderException {
-        int numberOfCertificates = 5;
-        int anotherNumberOfCertificates = 1;
-        List<String> truststoresPaths = createListOfPathsWithExtension(numberOfCertificates, JKS_EXTENSION);
-        List<String> truststorePasswordPaths = createListOfPathsWithExtension(numberOfCertificates, PASS_EXTENSION);
-        mockTruststorePaths(truststoresPaths, truststorePasswordPaths);
-
-        List<String> sourceKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(KEYSTORE_PATH,
-            numberOfCertificates, PEM_EXTENSION);
-        List<String> destKeystoresPairPaths = createListOfKeystorePairsPathsWithExtension(ANOTHER_KEYSTORE_PATH,
-            anotherNumberOfCertificates, PEM_EXTENSION);
-        mockKeystorePaths(sourceKeystoresPairPaths, destKeystoresPairPaths);
-
-        assertThatExceptionOfType(MergerConfigurationException.class)
-            .isThrownBy(factory::createConfiguration);
-    }
-
-    private void mockTruststorePaths(List<String> truststores, List<String> truststoresPasswords)
-        throws TruststoresPathsProviderException {
-        mockTruststores(truststores);
-        mockTruststoresPasswords(truststoresPasswords);
-    }
-
-    private void mockKeystorePaths(List<String> sourceKeystoresPairPaths, List<String> destKeystoresPairPaths)
-        throws TruststoresPathsProviderException {
-        mockKeystoreCopierSourcePaths(sourceKeystoresPairPaths);
-        mockKeystoreCopierDestinationPaths(destKeystoresPairPaths);
-    }
-
-    private void mockTruststores(List<String> truststores) throws TruststoresPathsProviderException {
-        when(certificatesPathsProvider.get(TRUSTSTORES_PATHS_ENV)).thenReturn(truststores);
-    }
-
-    private void mockTruststoresPasswords(List<String> truststoresPasswords) throws TruststoresPathsProviderException {
-        when(passwordsPathsProvider.get(TRUSTSTORES_PASSWORDS_PATHS_ENV)).thenReturn(truststoresPasswords);
-    }
-
-    private void mockKeystoreCopierSourcePaths(List<String> paths) throws TruststoresPathsProviderException {
-        when(copierPathsReader.get(KEYSTORE_SOURCE_PATHS_ENV)).thenReturn(paths);
-    }
-
-    private void mockKeystoreCopierDestinationPaths(List<String> paths) throws TruststoresPathsProviderException {
-        when(copierPathsReader.get(KEYSTORE_DESTINATION_PATHS_ENV)).thenReturn(paths);
-    }
-
-    private List<String> createListOfPathsWithExtension(int numberOfPaths, String passwordExtension) {
-        List<String> paths = new ArrayList<>();
-        while (numberOfPaths-- > 0) {
-            paths.add(BASE_TRUSTSTORE_PATH + numberOfPaths + passwordExtension);
-        }
-        return paths;
-    }
-
-    private List<String> createListOfKeystorePairsPathsWithExtension(String path, int numberOfPaths,
-        String certExtension) {
-        List<String> paths = new ArrayList<>();
-        String passExtension = certExtension.equalsIgnoreCase(".pem") ? certExtension : ".pass";
-        while (numberOfPaths-- > 0) {
-            paths.add(path + numberOfPaths + certExtension);
-            paths.add(ANOTHER_KEYSTORE_PATH + numberOfPaths + passExtension);
-        }
-        return paths;
-    }
-
-}
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderFactoryTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderFactoryTest.java
deleted file mode 100644
index 5a7e9cd0..00000000
--- a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderFactoryTest.java
+++ /dev/null
@@ -1,39 +0,0 @@
-/*============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.truststoremerger.configuration.path;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-import org.junit.jupiter.api.Test;
-import org.onap.oom.truststoremerger.configuration.path.env.EnvProvider;
-
-class DelimitedPathsReaderFactoryTest {
-
-    @Test
-    void shouldReturnObjectOfDelimitedPathsReaderType() {
-        // given
-        DelimitedPathsReaderFactory readerFactory = new DelimitedPathsReaderFactory(new EnvProvider());
-        //when, then
-        assertThat(readerFactory.createPasswordPathsReader()).isInstanceOf(DelimitedPathsReader.class);
-        assertThat(readerFactory.createCertificatePathsReader()).isInstanceOf(DelimitedPathsReader.class);
-        assertThat(readerFactory.createKeystoreCopierPathsReader()).isInstanceOf(DelimitedPathsReader.class);
-    }
-
-}
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderTest.java
deleted file mode 100644
index 408a7d6d..00000000
--- a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsReaderTest.java
+++ /dev/null
@@ -1,144 +0,0 @@
-/*============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.truststoremerger.configuration.path;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.mockito.Mockito.when;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PASSWORDS_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.ConfigurationEnvs.TRUSTSTORES_PATHS_ENV;
-import static org.onap.oom.truststoremerger.configuration.path.validation.ValidationFunctions.doesItContainValidCertificatesPaths;
-import static org.onap.oom.truststoremerger.configuration.path.validation.ValidationFunctions.doesItContainValidPasswordPaths;
-
-import java.util.Optional;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.extension.ExtendWith;
-import org.mockito.Mock;
-import org.mockito.junit.jupiter.MockitoExtension;
-import org.onap.oom.truststoremerger.configuration.exception.TruststoresPathsProviderException;
-import org.onap.oom.truststoremerger.configuration.path.env.EnvProvider;
-
-@ExtendWith(MockitoExtension.class)
-class DelimitedPathsReaderTest {
-
-    private static final String VALID_TRUSTSTORES = "/opt/app/certificates/truststore.jks:/opt/app/certificates/truststore.pem";
-    private static final String VALID_TRUSTSTORES_PASSWORDS = "/opt/app/certificates/truststore.pass:";
-    private static final String VALID_TRUSTSTORES_PASSWORDS_WITH_EMPTY_IN_THE_MIDDLE = "/opt/app/certificates/truststore.pass::/etc/truststore.pass";
-    private static final String INVALID_TRUSTSTORES = "/opt/app/certificates/truststore.jks:/opt/app/certificates/truststore.invalid";
-    private static final String INVALID_TRUSTSTORES_PASSWORDS = "/opt/app/certificates/truststore.pass:/.pass";
-
-    @Mock
-    private EnvProvider envProvider;
-    private DelimitedPathsReader delimitedPathsReader;
-
-    @Test
-    void shouldReturnCorrectListWhenTruststoresValid() throws TruststoresPathsProviderException {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidCertificatesPaths());
-        mockTruststoresEnv(VALID_TRUSTSTORES);
-
-        // when, then
-        assertThat(delimitedPathsReader.get(TRUSTSTORES_PATHS_ENV))
-            .containsSequence("/opt/app/certificates/truststore.jks",
-                "/opt/app/certificates/truststore.pem");
-    }
-
-    @Test
-    void shouldThrowExceptionWhenTruststoresPathsEnvIsEmpty() {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidCertificatesPaths());
-        mockTruststoresEnv("");
-
-        // when, then
-        assertThatExceptionOfType(TruststoresPathsProviderException.class)
-            .isThrownBy(() -> delimitedPathsReader.get(TRUSTSTORES_PATHS_ENV));
-    }
-
-    @Test
-    void shouldThrowExceptionWhenOneOfTruststoresPathsInvalid() {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidCertificatesPaths());
-        mockTruststoresEnv(INVALID_TRUSTSTORES);
-
-        // when, then
-        assertThatExceptionOfType(TruststoresPathsProviderException.class)
-            .isThrownBy(() -> delimitedPathsReader.get(TRUSTSTORES_PATHS_ENV));
-    }
-
-    @Test
-    void shouldReturnCorrectListWhenTruststoresPasswordsValid() throws TruststoresPathsProviderException {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidPasswordPaths());
-        mockTruststoresPasswordsEnv(VALID_TRUSTSTORES_PASSWORDS);
-
-        // when, then
-        assertThat(delimitedPathsReader.get(TRUSTSTORES_PASSWORDS_PATHS_ENV))
-            .containsSequence("/opt/app/certificates/truststore.pass", "");
-    }
-
-    @Test
-    void shouldReturnCorrectListWhenTruststoresPasswordsContainsEmptyPathsInTheMiddle()
-        throws TruststoresPathsProviderException {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidPasswordPaths());
-        mockTruststoresPasswordsEnv(VALID_TRUSTSTORES_PASSWORDS_WITH_EMPTY_IN_THE_MIDDLE);
-
-        // when, then
-        assertThat(delimitedPathsReader.get(TRUSTSTORES_PASSWORDS_PATHS_ENV)).containsSequence(
-            "/opt/app/certificates/truststore.pass",
-            "",
-            "/etc/truststore.pass"
-        );
-    }
-
-    @Test
-    void shouldThrowExceptionWhenTruststoresPasswordsPathEnvIsEmpty() {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidPasswordPaths());
-        mockTruststoresPasswordsEnv("");
-
-        // when, then
-        assertThatExceptionOfType(TruststoresPathsProviderException.class)
-            .isThrownBy(() -> delimitedPathsReader.get(TRUSTSTORES_PASSWORDS_PATHS_ENV));
-    }
-
-    @Test
-    void shouldThrowExceptionWhenOneOfTruststorePasswordPathsInvalid() {
-        // given
-        delimitedPathsReader = new DelimitedPathsReader(envProvider, doesItContainValidPasswordPaths());
-        mockTruststoresPasswordsEnv(INVALID_TRUSTSTORES_PASSWORDS);
-
-        // when, then
-        assertThatExceptionOfType(TruststoresPathsProviderException.class)
-            .isThrownBy(() -> delimitedPathsReader.get(TRUSTSTORES_PASSWORDS_PATHS_ENV));
-    }
-
-    private void mockTruststoresEnv(String truststores) {
-        mockEnv(TRUSTSTORES_PATHS_ENV, truststores);
-    }
-
-    private void mockTruststoresPasswordsEnv(String truststoresPasswords) {
-        mockEnv(TRUSTSTORES_PASSWORDS_PATHS_ENV, truststoresPasswords);
-    }
-
-    private void mockEnv(String envName, String truststores) {
-        when(envProvider.getEnv(envName)).thenReturn(Optional.of(truststores));
-    }
-}
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsSplitterTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsSplitterTest.java
new file mode 100644
index 00000000..22b5a7fc
--- /dev/null
+++ b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/DelimitedPathsSplitterTest.java
@@ -0,0 +1,107 @@
+/*============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.truststoremerger.configuration.path;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PASSWORDS_PATHS_ENV;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PATHS_ENV;
+
+import java.util.Optional;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.onap.oom.truststoremerger.configuration.exception.CertificatesPathsValidationException;
+
+@ExtendWith(MockitoExtension.class)
+class DelimitedPathsSplitterTest {
+
+    private static final String VALID_TRUSTSTORES = "/opt/app/certificates/truststore.jks:/opt/app/certificates/truststore.pem";
+    private static final String VALID_TRUSTSTORES_PASSWORDS = "/opt/app/certificates/truststore.pass:";
+    private static final String VALID_TRUSTSTORES_PASSWORDS_WITH_EMPTY_IN_THE_MIDDLE = "/opt/app/certificates/truststore.pass::/etc/truststore.pass";
+    private static final String INVALID_TRUSTSTORES = "/opt/app/certificates/truststore.jks:/opt/app/certificates/truststore.invalid";
+    private static final String INVALID_TRUSTSTORES_PASSWORDS = "/opt/app/certificates/truststore.pass:/.pass";
+
+    private DelimitedPathsSplitter delimitedPathsSplitter;
+
+    @BeforeEach
+    void setUp() {
+        delimitedPathsSplitter = new DelimitedPathsSplitter();
+    }
+
+    @Test
+    void shouldReturnCorrectListWhenTruststoresValid() {
+        // when, then
+        assertThat(delimitedPathsSplitter.getValidatedPaths(TRUSTSTORES_PATHS_ENV, Optional.of(VALID_TRUSTSTORES)))
+            .containsSequence("/opt/app/certificates/truststore.jks",
+                "/opt/app/certificates/truststore.pem");
+    }
+
+    @Test
+    void shouldThrowExceptionWhenTruststoresPathsEnvIsEmpty() {
+        // when, then
+        assertThatExceptionOfType(CertificatesPathsValidationException.class)
+            .isThrownBy(() -> delimitedPathsSplitter.getValidatedPaths(TRUSTSTORES_PATHS_ENV, Optional.of("")));
+    }
+
+    @Test
+    void shouldThrowExceptionWhenOneOfTruststoresPathsInvalid() {
+        // when, then
+        assertThatExceptionOfType(CertificatesPathsValidationException.class)
+            .isThrownBy(() -> delimitedPathsSplitter
+                .getValidatedPaths(TRUSTSTORES_PATHS_ENV, Optional.of(INVALID_TRUSTSTORES)));
+    }
+
+    @Test
+    void shouldReturnCorrectListWhenTruststoresPasswordsValid() {
+        // when, then
+        assertThat(delimitedPathsSplitter
+            .getValidatedPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV, Optional.of(VALID_TRUSTSTORES_PASSWORDS)))
+            .containsSequence("/opt/app/certificates/truststore.pass", "");
+    }
+
+    @Test
+    void shouldReturnCorrectListWhenTruststoresPasswordsContainsEmptyPathsInTheMiddle() {
+        // when, then
+        assertThat(delimitedPathsSplitter.getValidatedPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV,
+            Optional.of(VALID_TRUSTSTORES_PASSWORDS_WITH_EMPTY_IN_THE_MIDDLE))).containsSequence(
+            "/opt/app/certificates/truststore.pass",
+            "",
+            "/etc/truststore.pass"
+        );
+    }
+
+    @Test
+    void shouldThrowExceptionWhenTruststoresPasswordsPathEnvIsEmpty() {
+        // when, then
+        assertThatExceptionOfType(CertificatesPathsValidationException.class)
+            .isThrownBy(
+                () -> delimitedPathsSplitter.getValidatedPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV, Optional.of("")));
+    }
+
+    @Test
+    void shouldThrowExceptionWhenOneOfTruststorePasswordPathsInvalid() {
+        // when, then
+        assertThatExceptionOfType(CertificatesPathsValidationException.class)
+            .isThrownBy(() -> delimitedPathsSplitter
+                .getValidatedPaths(TRUSTSTORES_PASSWORDS_PATHS_ENV, Optional.of(INVALID_TRUSTSTORES_PASSWORDS)));
+    }
+}
diff --git a/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/env/EnvReaderTest.java b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/env/EnvReaderTest.java
new file mode 100644
index 00000000..0a654fe8
--- /dev/null
+++ b/trustStoreMerger/src/test/java/org/onap/oom/truststoremerger/configuration/path/env/EnvReaderTest.java
@@ -0,0 +1,62 @@
+/*============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.truststoremerger.configuration.path.env;
+
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.when;
+import static org.onap.oom.truststoremerger.configuration.model.EnvVariable.TRUSTSTORES_PASSWORDS_PATHS_ENV;
+
+import java.util.Optional;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+class EnvReaderTest {
+
+    private static final String SAMPLE_PASS_PATH = "/sample/path/trust.pass";
+    EnvReader provider;
+
+    @BeforeEach
+    void setUp() {
+        provider = Mockito.spy(EnvReader.class);
+    }
+
+    @Test
+    void shouldReturnOptionalWithEnv() {
+        // given
+        String envName = TRUSTSTORES_PASSWORDS_PATHS_ENV.name();
+        when(provider.getSystemEnv(envName)).thenReturn(Optional.of(SAMPLE_PASS_PATH));
+        // when
+        Optional<String> result = provider.getEnv(envName);
+        // then
+        assertThat(result).isEqualTo(Optional.of(SAMPLE_PASS_PATH));
+    }
+
+    @Test
+    void shouldReturnEmptyOptional() {
+        // given
+        String envName = TRUSTSTORES_PASSWORDS_PATHS_ENV.name();
+        // when
+        Optional<String> result = provider.getEnv(envName);
+        // then
+        assertThat(result).isEmpty();
+    }
+}