Added functionality to parse the MAINIFEST files to get the version of the protocols

* extend MsgService, add functionality to read protocol versions

* Added functionality to parse the MAINIFEST files to get the version of the protocols

* Added constant variable for string

* Fix: Added constant variable for string

Author: afshinhm-ericsson

.gitignore

@@ -7,3 +7,8 @@ gradlew.bat
 
 build/
 .gradle/
+/bin/
+
+.classpath
+.project
+.settings/

build.gradle

@@ -15,6 +15,9 @@ plugins{
     id 'eclipse'
 }
 
+apply plugin: 'java'
+apply plugin: 'eclipse'
+
 jar {
     baseName = 'remrem-shared'
     version =  '0.2.0'
@@ -24,12 +27,13 @@ group 'com.ericsson.eiffel.remrem'
 version '1.0-SNAPSHOT'
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '2.12'
+    gradleVersion = '3.1'
     distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
 }
 
 repositories {
     mavenCentral()
+    jcenter()
 }
 
 dependencies {

src/main/java/com/ericsson/eiffel/remrem/shared/VersionService.java

@@ -0,0 +1,80 @@
+package com.ericsson.eiffel.remrem.shared;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.jar.Attributes;
+import java.util.jar.JarFile;
+import java.util.jar.Manifest;
+
+/**
+ * This class will search in all registered jars and their manifest file for
+ * attribute Remrem-Version-Key. It will return a list with all versions found.
+ * 
+ * @author evasiba
+ *
+ */
+public class VersionService {
+
+    private static final String REMREM_VERSION_KEY = "remremVersionKey";
+    private static final String IS_ENDPOINT_VERSION = "isEndpointVersion";
+    private static final String ENDPOINT_VERSION = "endpointVersions";
+    private static final String SERVICE_VERSION = "serviceVersion";
+
+    /**
+     * This method will load and parse the MINIFEST files to get the version of
+     * the loaded messaging protocols. It is required to define the versions as
+     * mainifest attributes in the build.gradle or pom.xml files using
+     * attributes "remremVersionKey" and "isEndpointVersion" to specify the type
+     * of the protocol or service and if it is endpoint or not respectively.
+     * Example for build.gradle: manifest { attributes('remremVersionKey':
+     * 'semanticsVersion') attributes('semanticsVersion': version)
+     * attributes('isEndpointVersion': 'true') }
+     * 
+     * @return a map containing the protocol and service types with their
+     *         versions {"endpointVersions" : {"semanticsVersion" : "1.1.1"},
+     *         "serviceVersion": {"remremGenerateVersion": "0.1.1"}}
+     */
+    public static Map<String, Map<String, String>> getMessagingVersions() {
+        Enumeration<?> resEnum;
+        Map<String, Map<String, String>> versions = new HashMap<>();
+        Map<String, String> endpointVersions = new HashMap<String, String>();
+        Map<String, String> serviceVersion = new HashMap<String, String>();
+
+        try {
+            resEnum = Thread.currentThread().getContextClassLoader().getResources(JarFile.MANIFEST_NAME);
+            while (resEnum.hasMoreElements()) {
+                try {
+                    URL url = (URL) resEnum.nextElement();
+                    InputStream is = url.openStream();
+                    if (is != null) {
+                        Manifest manifest = new Manifest(is);
+                        Attributes mainAttribs = manifest.getMainAttributes();
+                        String versionKey = mainAttribs.getValue(REMREM_VERSION_KEY);
+
+                        if (versionKey != null) {
+                            String version = mainAttribs.getValue(versionKey);
+                            if (version != null) {
+                                if (mainAttribs.getValue(IS_ENDPOINT_VERSION) != null) {
+                                    endpointVersions.put(versionKey, version);
+                                } else {
+                                    serviceVersion.put(versionKey, version);
+                                }
+                            }
+                        }
+                    }
+                } catch (Exception e) {
+                    // Silently ignore wrong manifests on classpath?
+                }
+            }
+            versions.put(ENDPOINT_VERSION, endpointVersions);
+            versions.put(SERVICE_VERSION, serviceVersion);
+        } catch (IOException e1) {
+            // Silently ignore wrong manifests on classpath?
+        }
+        return versions;
+    }
+}