diff --git a/websockets/build.gradle b/websockets/build.gradle
index 8541fc8..7316d34 100644
--- a/websockets/build.gradle
+++ b/websockets/build.gradle
@@ -1,12 +1,12 @@
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion '26.0.2'
+    compileSdkVersion 27
+    buildToolsVersion '27.0.3'
 
     defaultConfig {
         minSdkVersion 14
-        targetSdkVersion 25
+        targetSdkVersion 27
         versionCode 1
         versionName "1.0"
 
@@ -22,11 +22,12 @@ android {
 }
 
 dependencies {
-    compile fileTree(include: ['*.jar'], dir: 'libs')
-    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+    implementation fileTree(include: ['*.jar'], dir: 'libs')
+    androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    testCompile 'junit:junit:4.12'
-    compile 'org.codehaus.jackson:jackson-mapper-asl:1.9.13'
-    compile 'com.google.code.gson:gson:2.8.1'
+    testImplementation 'junit:junit:4.12'
+    implementation 'org.codehaus.jackson:jackson-mapper-asl:1.9.13'
+    implementation 'com.google.code.gson:gson:2.8.1'
+    implementation 'org.apache.commons:commons-lang3:3.6'
 }
diff --git a/websockets/src/main/java/com/craftsman/websockets/Ws.java b/websockets/src/main/java/com/craftsman/websockets/Ws.java
index d42abee..248c308 100644
--- a/websockets/src/main/java/com/craftsman/websockets/Ws.java
+++ b/websockets/src/main/java/com/craftsman/websockets/Ws.java
@@ -1,16 +1,16 @@
 package com.craftsman.websockets;
 
-/**
- * Created by ALI SHADAÏ (Software Craftman) on 15/09/2017.
- */
 
+import java.util.List;
+
+@SuppressWarnings("JavaDoc")
 public interface Ws {
 
     /**
      *
      * @return
      */
-     Ws connect() throws Exception;
+    Ws connect() throws Exception;
 
 
     /**
@@ -18,7 +18,7 @@ public interface Ws {
      * @param channelPath
      * @param wsListner
      */
-    <T> Ws on(String channelPath,Class<T> exceptedDataType, WsListner<T> wsListner);
+    <T> Ws on(String channelPath, Class<T> exceptedDataType, WsListner<T> wsListner);
 
 
     /**
@@ -27,7 +27,15 @@ public interface Ws {
      * @param wsListner
      * @return
      */
-     Ws on(String channelPath, WsListner wsListner);
+    Ws on(String channelPath, WsListner wsListner);
+
+    /**
+     * @param channelPath
+     * @return
+     */
+    Ws unsubscribe(String channelPath);
+
+    Ws unsubscribe(List<String> channelPath);
 
     /**
      *
@@ -48,7 +56,7 @@ public interface Ws {
      * @param channelPath
      * @param o
      */
-    void send(String channelPath,Object o);
+    void send(String channelPath, Object o);
 
 
     /**
@@ -61,7 +69,7 @@ public interface Ws {
      */
     interface WsListner<T> {
 
-        void onEvent(String eventUri,T data);
+        void onEvent(String eventUri, T data);
     }
 
 
@@ -73,4 +81,4 @@ public WsImpl from(String websocketServerUri){
             return new WsImpl(websocketServerUri);
         }
     }
-}
+}
\ No newline at end of file
diff --git a/websockets/src/main/java/com/craftsman/websockets/WsImpl.java b/websockets/src/main/java/com/craftsman/websockets/WsImpl.java
index 025b729..063dcb1 100644
--- a/websockets/src/main/java/com/craftsman/websockets/WsImpl.java
+++ b/websockets/src/main/java/com/craftsman/websockets/WsImpl.java
@@ -1,31 +1,63 @@
 package com.craftsman.websockets;
 
+import android.os.Handler;
 import android.util.Log;
 
 import com.google.gson.Gson;
 
+import org.apache.commons.lang3.StringUtils;
+
 import java.util.ArrayList;
 import java.util.List;
 
 import de.tavendo.autobahn.Autobahn;
 import de.tavendo.autobahn.AutobahnConnection;
 
-/**
- * Created by ALI SHADAÏ (Software Craftman) on 15/09/2017.
- */
-
+@SuppressWarnings("unchecked")
 public class WsImpl implements Ws {
+    private final String TAG = "Web Socket Impl";
+    private final List<Payload> subscriptions = new ArrayList<>();
+    private Handler mainHandler = new Handler();
+    private AutobahnConnection autobahnConnection = new AutobahnConnection();
+    private String serverUrl;
+    private Runnable handleSocketReconnection = new Runnable() {
+        @Override
+        public void run() {
+            try {
+                if (autobahnConnection != null && !autobahnConnection.isConnected())
+                    connect();
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+    };
 
-    final String TAG = "Web Socket Impl";
-
-    AutobahnConnection autobahnConnection = new AutobahnConnection();
-    final List<Payload> subscriptions = new ArrayList<>();
-    String serverUrl;
-
-    public WsImpl(String websocketServerUri) {
+    WsImpl(String websocketServerUri) {
         serverUrl = websocketServerUri;
     }
 
+    public void changeSocketURI(String host, String port) throws Exception {
+
+        if (serverUrl != null && !serverUrl.isEmpty()) {
+
+            if (autobahnConnection != null && autobahnConnection.isConnected()) {
+                end();
+            }
+
+            String[] spliter = serverUrl.split(":");
+            if (host != null && !host.isEmpty()) {
+                spliter[1] = "//" + host;
+            }
+
+            if (port != null && !port.isEmpty()) {
+                spliter[2] = port;
+            }
+
+            serverUrl = StringUtils.join(spliter, ":");
+
+            connect();
+        }
+    }
 
     @Override
     public Ws connect() throws Exception {
@@ -49,7 +81,6 @@ public void onEvent(String s, Object o) {
                                         (payload.objectType != null) ?
                                                 new Gson().fromJson(o.toString(),payload.objectType)
                                                  : o);
-
                             }
                             catch (Exception e){
                                 e.printStackTrace();
@@ -61,11 +92,11 @@ public void onEvent(String s, Object o) {
             @Override
             public void onClose(int i, String s) {
                 //force recnnection to web socket
-                Log.i(TAG,"Disconnected");
-                try {
-                  if(!autobahnConnection.isConnected()) connect();
-                } catch (Exception e) {
-                    e.printStackTrace();
+                Log.e(TAG, "Disconnected; Code " + i);
+
+                if (i == 1 || i == 3 || i == 2 || i == 4 || i == 5) {
+                    mainHandler.removeCallbacks(handleSocketReconnection);
+                    mainHandler.postDelayed(handleSocketReconnection, 15000);
                 }
             }
         });
@@ -74,9 +105,9 @@ public void onClose(int i, String s) {
 
     @Override
     public <T> Ws on(final String channelPath, final Class<T> exceptedDataType, final WsListner<T> wsListner) {
+        subscriptions.add(new Payload<>(channelPath, exceptedDataType, wsListner));
 
-        if(!autobahnConnection.isConnected()){
-            subscriptions.add(new Payload<>(channelPath,exceptedDataType,wsListner));
+        if (!autobahnConnection.isConnected()) {
             return this;
         }
         else {
@@ -91,10 +122,11 @@ public void onEvent(String s, Object o) {
         return this;
     }
 
+
     @Override
     public Ws on(String channelPath, final WsListner wsListner) {
-        if(!autobahnConnection.isConnected()){
-            subscriptions.add(new Payload<>(channelPath,null,wsListner));
+        subscriptions.add(new Payload<>(channelPath, null, wsListner));
+        if (!autobahnConnection.isConnected()) {
             return this;
         }
         else autobahnConnection.subscribe(channelPath, Object.class, new Autobahn.EventHandler() {
@@ -107,6 +139,29 @@ public void onEvent(String s, Object o) {
         return this;
     }
 
+    @Override
+    public Ws unsubscribe(String channelPath) {
+        for (Payload payload : subscriptions) {
+            if (StringUtils.equals(payload.channel, channelPath)) {
+                if (autobahnConnection != null) {
+                    if (autobahnConnection.isConnected())
+                        autobahnConnection.unsubscribe(channelPath);
+
+                    subscriptions.remove(payload);
+                }
+            }
+        }
+        return this;
+    }
+
+    @Override
+    public Ws unsubscribe(List<String> channelPath) {
+        for (String payload : channelPath) {
+            unsubscribe(payload);
+        }
+        return this;
+    }
+
     @Override
     public void send( String text) {
         if(autobahnConnection.isConnected())
@@ -129,21 +184,19 @@ public void send(String channelPath, Object o) {
     public void end() {
         if(autobahnConnection != null && autobahnConnection.isConnected()) {
             autobahnConnection.unsubscribe();
-            autobahnConnection = null;
+            autobahnConnection.disconnect();
         }
     }
 
     final private class Payload<T>{
-        String channel;
-        Class<T> objectType;
-        WsListner listner;
-
-
+        private String channel;
+        private Class<T> objectType;
+        private WsListner listner;
 
-        public Payload(String channel, Class<T> objectType, WsListner listner) {
+        Payload(String channel, Class<T> objectType, WsListner listner) {
             this.channel = channel;
             this.objectType = objectType;
             this.listner = listner;
         }
     }
-}
+}
\ No newline at end of file
diff --git a/websockets/websockets.iml b/websockets/websockets.iml
new file mode 100644
index 0000000..2689591
--- /dev/null
+++ b/websockets/websockets.iml
@@ -0,0 +1,134 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module external.linked.project.id=":websockets" external.linked.project.path="$MODULE_DIR$" external.root.project.path="$MODULE_DIR$/../.." external.system.id="GRADLE" type="JAVA_MODULE" version="4">
+  <component name="FacetManager">
+    <facet type="android-gradle" name="Android-Gradle">
+      <configuration>
+        <option name="GRADLE_PROJECT_PATH" value=":websockets" />
+      </configuration>
+    </facet>
+    <facet type="android" name="Android">
+      <configuration>
+        <option name="SELECTED_BUILD_VARIANT" value="debug" />
+        <option name="ASSEMBLE_TASK_NAME" value="assembleDebug" />
+        <option name="COMPILE_JAVA_TASK_NAME" value="compileDebugSources" />
+        <afterSyncTasks>
+          <task>generateDebugSources</task>
+        </afterSyncTasks>
+        <option name="ALLOW_USER_CONFIGURATION" value="false" />
+        <option name="MANIFEST_FILE_RELATIVE_PATH" value="/src/main/AndroidManifest.xml" />
+        <option name="RES_FOLDER_RELATIVE_PATH" value="/src/main/res" />
+        <option name="RES_FOLDERS_RELATIVE_PATH" value="file://$MODULE_DIR$/src/main/res" />
+        <option name="ASSETS_FOLDER_RELATIVE_PATH" value="/src/main/assets" />
+        <option name="PROJECT_TYPE" value="1" />
+      </configuration>
+    </facet>
+  </component>
+  <component name="NewModuleRootManager" LANGUAGE_LEVEL="JDK_1_7">
+    <output url="file://$MODULE_DIR$/build/intermediates/classes/debug" />
+    <output-test url="file://$MODULE_DIR$/build/intermediates/classes/test/debug" />
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/apt/debug" isTestSource="false" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/r/debug" isTestSource="false" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/aidl/debug" isTestSource="false" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/buildConfig/debug" isTestSource="false" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/rs/debug" isTestSource="false" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/rs/debug" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/resValues/debug" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/apt/androidTest/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/r/androidTest/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/aidl/androidTest/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/buildConfig/androidTest/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/rs/androidTest/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/rs/androidTest/debug" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/resValues/androidTest/debug" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/source/apt/test/debug" isTestSource="true" generated="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/res" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/resources" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/assets" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/aidl" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/java" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/rs" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/debug/shaders" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestDebug/shaders" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/shaders" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/res" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/resources" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/assets" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/aidl" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/rs" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/shaders" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/shaders" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/shaders" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/annotations" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/attr" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/check-manifest" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/classes" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/extractedTypedefs" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/incremental" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/intermediate-jars" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/javaPrecompile" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/jniLibs" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/library_and_local_jars_jni" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/lint" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/manifests" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/packaged-aidl" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/packaged-classes" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/packagedAssets" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/packaged_res" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/public_res" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/res" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/rs" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/shaders" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/symbols" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/transforms" />
+      <excludeFolder url="file://$MODULE_DIR$/build/outputs" />
+      <excludeFolder url="file://$MODULE_DIR$/build/tmp" />
+    </content>
+    <orderEntry type="jdk" jdkName="Android API 27 Platform" jdkType="Android SDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="Gradle: __local_aars__:/home/fasegiar/Documents/open_si/E-Conseil/WebSocketAndroidClient/websockets/libs/autobahn-0.5.0.jar:unspecified@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.google.code.findbugs:jsr305:2.0.1@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: javax.inject:javax.inject:1@jar" level="project" />
+    <orderEntry type="library" name="Gradle: com.google.code.gson:gson:2.8.1@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.android.support.test.espresso:espresso-idling-resource-2.2.2" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: junit:junit:4.12@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: org.hamcrest:hamcrest-core:1.3@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: javax.annotation:javax.annotation-api:1.2@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.android.support.test:runner-0.5" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.android.support.test.espresso:espresso-core-2.2.2" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.android.support.test:exposed-instrumentation-api-publish-0.5" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: org.hamcrest:hamcrest-library:1.3@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: org.hamcrest:hamcrest-integration:1.3@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.squareup:javawriter:2.1.1@jar" level="project" />
+    <orderEntry type="library" name="Gradle: org.codehaus.jackson:jackson-mapper-asl:1.9.13@jar" level="project" />
+    <orderEntry type="library" scope="TEST" name="Gradle: com.android.support.test:rules-0.5" level="project" />
+    <orderEntry type="library" name="Gradle: org.codehaus.jackson:jackson-core-asl:1.9.13@jar" level="project" />
+    <orderEntry type="library" name="Gradle: org.apache.commons:commons-lang3:3.6@jar" level="project" />
+  </component>
+</module>
\ No newline at end of file