+ new getId() JNI method

kiwix.c

@@ -81,6 +81,23 @@ JNIEXPORT jstring JNICALL Java_org_kiwix_kiwixmobile_JNIKiwix_getMainPage(JNIEnv
   return url;
 }
 
+JNIEXPORT jstring JNICALL Java_org_kiwix_kiwixmobile_JNIKiwix_getId(JNIEnv *env, jobject obj) {
+  jstring id;
+  
+  pthread_mutex_lock(&readerLock);
+  if (reader != NULL) {
+    try {
+      std::string cId = reader->getId();
+      id = c2jni(cId, env);
+    } catch (exception &e) {
+      std::cerr << e.what() << std::endl;
+    }
+  }
+  pthread_mutex_unlock(&readerLock);
+  
+  return id;
+}
+
 JNIEXPORT jboolean JNICALL Java_org_kiwix_kiwixmobile_JNIKiwix_loadZIM(JNIEnv *env, jobject obj, jstring path) {
   jboolean retVal = JNI_TRUE;
   std::string cPath = jni2c(path, env);

src/org/kiwix/kiwixmobile/JNIKiwix.java

@@ -1,6 +1,7 @@
 package org.kiwix.kiwixmobile;
 public class JNIKiwix {
     public native String getMainPage();
+    public native String getId();
     public native boolean loadZIM(String path);
     public native byte[] getContent(String url, JNIKiwixString mimeType, JNIKiwixInt size);
     public native boolean searchSuggestions(String prefix, int count);

src/org/kiwix/kiwixmobile/ZimContentProvider.java

@@ -67,6 +67,14 @@ public class ZimContentProvider extends ContentProvider {
 		}			
 	}
 
+    public static String getId() {
+		if (jniKiwix==null || zimFileName==null)
+			return null;
+		else {
+			return jniKiwix.getId();
+		}			
+	}
+	
 	public static boolean searchSuggestions(String prefix, int count) {
 		if (jniKiwix==null || zimFileName==null)
 			return false;