Abstract utility classes for re-use

When looking at the existing uses of BundleActivator(s), it became
immediately clear that other parts of the code have a strategy based
properties file resolution very similar to those abstracted by dblib.
This change aggregates a separate utils bundle for this functionality,
which is further abstracted for potential reuse with other use cases.

The next use case is in the sli bundle, which will be handled in
a follow-up patch.

Issue-Id: SDNC-54
Change-Id: Ie4d4bb679617474b1983e6044c08cca1742b9893
Signed-off-by: Ryan Goulding <ryandgoulding@gmail.com>

6 files changed, 10 insertions, 324 deletions

diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/DBLIBResourceProvider.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/DBLIBResourceProvider.java
index 062cd8408..8e0b534f0 100644
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/DBLIBResourceProvider.java
+++ b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/DBLIBResourceProvider.java
@@ -27,11 +27,11 @@ import java.util.Optional;
 import java.util.Properties;
 import java.util.Vector;
 
-import org.onap.ccsdk.sli.core.dblib.propertiesfileresolver.DblibDefaultFileResolver;
-import org.onap.ccsdk.sli.core.dblib.propertiesfileresolver.DblibEnvVarFileResolver;
-import org.onap.ccsdk.sli.core.dblib.propertiesfileresolver.DblibJREFileResolver;
-import org.onap.ccsdk.sli.core.dblib.propertiesfileresolver.DblibKarafRootFileResolver;
-import org.onap.ccsdk.sli.core.dblib.propertiesfileresolver.DblibPropertiesFileResolver;
+import org.onap.ccsdk.sli.core.utils.dblib.DblibDefaultFileResolver;
+import org.onap.ccsdk.sli.core.utils.dblib.DblibEnvVarFileResolver;
+import org.onap.ccsdk.sli.core.utils.JREFileResolver;
+import org.onap.ccsdk.sli.core.utils.KarafRootFileResolver;
+import org.onap.ccsdk.sli.core.utils.PropertiesFileResolver;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -58,7 +58,7 @@ public class DBLIBResourceProvider {
     /**
      * A prioritized list of strategies for resolving dblib properties files.
      */
-    private Vector<DblibPropertiesFileResolver> dblibPropertiesFileResolvers = new Vector();
+    private Vector<PropertiesFileResolver> dblibPropertiesFileResolvers = new Vector();
 
     /**
      * The configuration properties for the db connection.
@@ -75,10 +75,10 @@ public class DBLIBResourceProvider {
         dblibPropertiesFileResolvers.add(new DblibDefaultFileResolver(
                 "Using property file (1) from default directory"
         ));
-        dblibPropertiesFileResolvers.add(new DblibJREFileResolver(
-                "Using property file (2) from JRE argument"
+        dblibPropertiesFileResolvers.add(new JREFileResolver(
+                "Using property file (2) from JRE argument", DBLIBResourceProvider.class
         ));
-        dblibPropertiesFileResolvers.add(new DblibKarafRootFileResolver(
+        dblibPropertiesFileResolvers.add(new KarafRootFileResolver(
                 "Using property file (4) from karaf root", this));
 
         // determines properties file as according to the priority described in the class header comment
@@ -141,7 +141,7 @@ public class DBLIBResourceProvider {
      */
     File determinePropertiesFile(final DBLIBResourceProvider dblibResourceProvider) {
 
-        for (final DblibPropertiesFileResolver dblibPropertiesFileResolver : dblibPropertiesFileResolvers) {
+        for (final PropertiesFileResolver dblibPropertiesFileResolver : dblibPropertiesFileResolvers) {
             final Optional<File> fileOptional = dblibPropertiesFileResolver.resolveFile(DBLIB_PROP_FILE_NAME);
             if (fileOptional.isPresent()) {
                 return reportSuccess(dblibPropertiesFileResolver.getSuccessfulResolutionMessage(), fileOptional);
diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibDefaultFileResolver.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibDefaultFileResolver.java
deleted file mode 100644
index a7797d9f7..000000000
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibDefaultFileResolver.java
+++ /dev/null
@@ -1,63 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * onap
- * ================================================================================
- * Copyright (C) 2016 - 2017 ONAP
- * ================================================================================
- * 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.ccsdk.sli.core.dblib.propertiesfileresolver;
-
-import java.io.File;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.Optional;
-
-/**
- * Resolves dblib properties files relative to the default file path.  In Unix, this is represented by:
- * <code>/opt/sdnc/data/properties</code>
- */
-public class DblibDefaultFileResolver implements DblibPropertiesFileResolver {
-
-    /**
-     * Default path to look for the configuration directory
-     */
-    private static final Path DEFAULT_DBLIB_PROP_DIR = Paths.get("opt", "sdnc", "data", "properties");
-
-    private final String successMessage;
-
-    public DblibDefaultFileResolver(final String successMessage) {
-        this.successMessage = successMessage;
-    }
-
-    /**
-     * Parse a properties file location based on the default properties location
-     *
-     * @return an Optional File containing the location if it exists, or an empty Optional
-     */
-    @Override
-    public Optional<File> resolveFile(final String dblibFileName) {
-        final File fileFromDefaultDblibDir = DEFAULT_DBLIB_PROP_DIR.resolve(dblibFileName).toFile();
-        if (fileFromDefaultDblibDir.exists()) {
-            Optional.of(fileFromDefaultDblibDir);
-        }
-        return Optional.empty();
-    }
-
-    @Override
-    public String getSuccessfulResolutionMessage() {
-        return this.successMessage;
-    }
-}
diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibEnvVarFileResolver.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibEnvVarFileResolver.java
deleted file mode 100644
index 0b69109f9..000000000
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibEnvVarFileResolver.java
+++ /dev/null
@@ -1,69 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * onap
- * ================================================================================
- * Copyright (C) 2016 - 2017 ONAP
- * ================================================================================
- * 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.ccsdk.sli.core.dblib.propertiesfileresolver;
-
-import com.google.common.base.Strings;
-
-import java.io.File;
-import java.nio.file.Paths;
-import java.util.Optional;
-
-/**
- * Resolves dblib properties files relative to the directory identified by the <code>SDNC_CONFIG_DIR</code>
- * environment variable.
- */
-public class DblibEnvVarFileResolver implements DblibPropertiesFileResolver {
-
-    /**
-     * Key for environment variable representing the configuration directory
-     */
-    private static final String SDNC_CONFIG_DIR_PROP_KEY = "SDNC_CONFIG_DIR";
-
-    private final String successMessage;
-
-    public DblibEnvVarFileResolver(final String successMessage) {
-        this.successMessage = successMessage;
-    }
-
-    /**
-     * Parse a properties file location based on System environment variable
-     *
-     * @return an Optional File containing the location if it exists, or an empty Optional
-     */
-    @Override
-    public Optional<File> resolveFile(final String dblibFileName) {
-        // attempt to resolve the property directory from the corresponding environment variable
-        final String propDirectoryFromEnvVariable = System.getenv(SDNC_CONFIG_DIR_PROP_KEY);
-        final File fileFromEnvVariable;
-        if (!Strings.isNullOrEmpty(propDirectoryFromEnvVariable)) {
-            fileFromEnvVariable = Paths.get(propDirectoryFromEnvVariable).resolve(dblibFileName).toFile();
-            if(fileFromEnvVariable.exists()) {
-                return Optional.of(fileFromEnvVariable);
-            }
-        }
-        return Optional.empty();
-    }
-
-    @Override
-    public String getSuccessfulResolutionMessage() {
-        return this.successMessage;
-    }
-}
diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibJREFileResolver.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibJREFileResolver.java
deleted file mode 100644
index 673ccbf03..000000000
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibJREFileResolver.java
+++ /dev/null
@@ -1,73 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * onap
- * ================================================================================
- * Copyright (C) 2016 - 2017 ONAP
- * ================================================================================
- * 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.ccsdk.sli.core.dblib.propertiesfileresolver;
-
-import java.io.File;
-import java.net.URISyntaxException;
-import java.net.URL;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.Optional;
-import org.onap.ccsdk.sli.core.dblib.DBLIBResourceProvider;
-import org.osgi.framework.FrameworkUtil;
-
-/**
- * Resolves dblib properties files relative to the directory identified by the JRE property
- * <code>dblib.properties</code>.
- */
-public class DblibJREFileResolver implements DblibPropertiesFileResolver {
-
-    /**
-     * Key for JRE argument representing the configuration directory
-     */
-    private static final String DBLIB_JRE_PROPERTY_KEY = "dblib.properties";
-
-    private final String successMessage;
-
-    public DblibJREFileResolver(final String successMessage) {
-        this.successMessage = successMessage;
-    }
-
-    /**
-     * Parse a properties file location based on JRE argument
-     *
-     * @return an Optional File containing the location if it exists, or an empty Optional
-     */
-    @Override
-    public Optional<File> resolveFile(final String dblibFileName) {
-        final URL jreArgumentUrl = FrameworkUtil.getBundle(DBLIBResourceProvider.class)
-                .getResource(DBLIB_JRE_PROPERTY_KEY);
-        try {
-            if (jreArgumentUrl == null) {
-                return Optional.empty();
-            }
-            final Path dblibPath = Paths.get(jreArgumentUrl.toURI());
-            return Optional.of(dblibPath.resolve(dblibFileName).toFile());
-        } catch(final URISyntaxException e) {
-            return Optional.empty();
-        }
-    }
-
-    @Override
-    public String getSuccessfulResolutionMessage() {
-        return this.successMessage;
-    }
-}
diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibKarafRootFileResolver.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibKarafRootFileResolver.java
deleted file mode 100644
index d2b164e3b..000000000
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibKarafRootFileResolver.java
+++ /dev/null
@@ -1,64 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * onap
- * ================================================================================
- * Copyright (C) 2016 - 2017 ONAP
- * ================================================================================
- * 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.ccsdk.sli.core.dblib.propertiesfileresolver;
-
-import java.io.File;
-import java.net.URL;
-import java.util.Optional;
-import org.onap.ccsdk.sli.core.dblib.DBLIBResourceProvider;
-
-/**
- * Resolves dblib properties files relative to the karaf root directory.
- */
-public class DblibKarafRootFileResolver implements DblibPropertiesFileResolver {
-
-    final DBLIBResourceProvider dblibResourceProvider;
-
-    private final String successMessage;
-
-    public DblibKarafRootFileResolver(final String successMessage, final DBLIBResourceProvider dblibResourceProvider) {
-        this.successMessage = successMessage;
-        this.dblibResourceProvider = dblibResourceProvider;
-    }
-
-    /**
-     * Parse a properties file location relative to the karaf root
-     *
-     * @return an Optional File containing the location if it exists, or an empty Optional
-     */
-    @Override
-    public Optional<File> resolveFile(final String dblibFileName) {
-        final URL fromKarafRoot = dblibResourceProvider.getClass().getResource(dblibFileName);
-        if (fromKarafRoot != null) {
-            final File propertiesFile = new File(fromKarafRoot.getFile());
-            if (propertiesFile.exists()) {
-                return Optional.of(propertiesFile);
-            }
-            return Optional.empty();
-        }
-        return Optional.empty();
-    }
-
-    @Override
-    public String getSuccessfulResolutionMessage() {
-        return this.successMessage;
-    }
-}
diff --git a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibPropertiesFileResolver.java b/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibPropertiesFileResolver.java
deleted file mode 100644
index 97ab08acf..000000000
--- a/dblib/provider/src/main/java/org/onap/ccsdk/sli/core/dblib/propertiesfileresolver/DblibPropertiesFileResolver.java
+++ /dev/null
@@ -1,45 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * onap
- * ================================================================================
- * Copyright (C) 2016 - 2017 ONAP
- * ================================================================================
- * 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.ccsdk.sli.core.dblib.propertiesfileresolver;
-
-import java.io.File;
-import java.util.Optional;
-
-/**
- * Strategy for resolving dblib properties.
- */
-public interface DblibPropertiesFileResolver {
-
-    /**
-     * Resolve dblib properties file.
-     *
-     * @param dblibFileName the name of the file to look for at the specific location.
-     * @return An optional File or empty.
-     */
-    Optional<File> resolveFile(final String dblibFileName);
-
-    /**
-     * A success message, used only for logging now.
-     *
-     * @return a success message, used only for logging now.
-     */
-    String getSuccessfulResolutionMessage();
-}