AllJoyn+Android开发案例-android跨设备调用方法

项目需要涉及AllJoyn开源物联网框架。前面主要了解了一些AllJoyn基本的概念，像总线，总线附件，总线对象，总线接口这样的概念，以及之间的关系和跨设备、平台的调用功能。项目最终的目的实现是，跨平台的方法调用如：windows调用android，以及对于设备事件的订阅功能。

入手的步骤：

1.实现android端的跨设备方法（自定义）调用案例-java

2.实现windows端的跨设备方法（自定义）调用案例-c++

3.实现windows端和android端的跨设备方法调用案例-（window用C++，android用java）

4.结合实际项目实现跨平台、跨设备的方法调用和订阅功能

现阶段我们来尝试实现android端的跨设备方法（自定义）调用案例-java

上面一篇关于博客--AllJoyn+Android开发的一般步骤，主要概念上描述了如何实现调用，这篇文章我们结合android代码实现，走一遍流程，加深理解和记忆。参考地址http://blog.csdn.net/jsjdtb356/article/details/51084886。

官网参考地址（很重要）：https://allseenalliance.org/framework/documentation/develop/api-guide/core/java

开源代码（core API+很多实例-android studio可运行）：https://allseenalliance.org/framework/download

step1：

新建android studio project，选择file/project structrue 设置好java sdk，android sdk，android ndk的路径。

step2：

添加两个库文件，一个是alljoyn.jar库文件，一个是liballjoyn_java.so库文件，下载地址是https://allseenalliance.org/framework/download。版本我下载的是15.04，如下图。

我的.jar的绝对路径：G:\alljoyn\alljoyn-android\core\alljoyn-15.04.00b-rel\java\jar\alljoyn.jar

我的.so的绝对路径：G:\alljoyn\alljoyn-android\core\alljoyn-15.04.00b-rel\java\lib\liballjoyn_java.so

大家根据自己的解压位置去找就好了。

添加到工程后如下图所示：

project视图下，添加的路径和文件夹名称，没有文件夹则建立对应名称的文件夹。然后将jar添加作库。

step3：

实现流程大致画一个示意图：

server代码实现：一个activity用于交互，button开启一个service；service中具体实现alljoyn代码；一个总线接口，总线对象要实现的接口；service上代码如下。

package com.example.siemens.testgetmethod;import android.app.Service;
import android.content.Intent;
import android.net.wifi.WifiConfiguration;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.widget.Toast;import org.alljoyn.bus.BusAttachment;
import org.alljoyn.bus.BusObject;
import org.alljoyn.bus.Mutable;
import org.alljoyn.bus.SessionOpts;
import org.alljoyn.bus.SessionPortListener;
import org.alljoyn.bus.Status;import javax.net.ssl.SSLEngineResult;public class MyService extends Service {private final String TAG="MyService";public MyService() {
//        super();}@Overridepublic IBinder onBind(Intent intent) {// TODO: Return the communication channel to the service.
//        throw new UnsupportedOperationException("Not yet implemented");return null;}public int onStartCommand(Intent intent, int flags, int startId) {
//        Log.i(TAG, "onStartCommand()");return START_STICKY;}public void onDestroy() {
//        backgroundHandler.exit();}public void onCreate(){Log.i(TAG,"onCreate method.");//mbus初始化mBus=new BusAttachment(getPackageName(),BusAttachment.RemoteMessage.Receive);startBusThread();if(backgroundHandler!=null)backgroundHandler.connect();elsereturn;}private void startBusThread(){HandlerThread handlerThread=new HandlerThread("My HandlerThread");handlerThread.start();Looper loop=handlerThread.getLooper();backgroundHandler=new BackgroundHandler(loop);Log.i(TAG,"startBusThread method.");}//请求都在线程中执行private BackgroundHandler backgroundHandler=null;private final int CONNECT=2;//私有内部不可变类private final class BackgroundHandler extends Handler{public BackgroundHandler(Looper looper){super(looper);}public void connect(){Log.i(TAG,"backgroundHandler.connect()");Message msg=backgroundHandler.obtainMessage(CONNECT);//相当于message.what=2;backgroundHandler.sendMessage(msg);}public void handleMessage(Message msg){switch(msg.what){case CONNECT:doConnect();break;default:break;}}}//创建总线附件对象,getPackageName()出现NullPointerException异常,先于构造函数执行，此时对象为null，所以放到oncreate里边去
//    private BusAttachment mBus=new BusAttachment(getPackageName(),BusAttachment.RemoteMessage.Receive);private BusAttachment mBus=null;//创建总线对象private MyBusObject myBusObject=new MyBusObject();//总线对象类，实现总线接口和总线对象接口class MyBusObject implements MyInterface,BusObject{
//        public void show(String args){
//            Toast.makeText(getApplicationContext(),args,Toast.LENGTH_SHORT).show();     //会调用的远程方法
//
//        }
//
//        public int add(int a,int b){                        //会调用的远程方法
//            return a+b;
//        }public String cat(String a,String b){a=a.replace('H','T');b=b.replace('W','B');return a+b;}}//session的端口号private static final short CONTACT_PORT=42;//总线对象，总线附件等连接到总线上的实现函数，创建的是serviceprivate void doConnect(){org.alljoyn.bus.alljoyn.DaemonInit.PrepareDaemon(getApplicationContext());  //启动守护进程Status status=mBus.registerBusObject(myBusObject,"/myBusObject");                     //注册总线对象if (Status.OK != status) {System.out.println("BusAttachment.registerBusObject() failed: " + status);System.exit(0);return;}//总线附件连接到总线上status=mBus.connect();if (status != Status.OK) {Log.i(TAG,"BusAttachment connect to bus failed.");System.exit(0);return;}//通信的session port 设置Mutable.ShortValue contactPort = new Mutable.ShortValue(CONTACT_PORT);SessionOpts sessionOpts = new SessionOpts();sessionOpts.traffic = SessionOpts.TRAFFIC_MESSAGES;sessionOpts.isMultipoint = false;sessionOpts.proximity = SessionOpts.PROXIMITY_ANY;sessionOpts.transports = SessionOpts.TRANSPORT_ANY;//绑定通信的session portstatus=mBus.bindSessionPort(contactPort,sessionOpts,new SessionPortListener(){@Overridepublic boolean acceptSessionJoiner(short sessionPort, String joiner, SessionOpts sessionOpts){if (sessionPort == CONTACT_PORT) {return true;} else {return false;}}});if (status != Status.OK) {Log.i(TAG,"bind certain session port failed.");System.exit(0);return;}//向总线请求一个名称int flags = 0; //do not use any request name flagsstatus = mBus.requestName("com.test.well.known.name", flags);if (status != Status.OK) {Log.i(TAG,"request name from bus failed.");System.exit(0);return;}//在总线上宣告name的存在status = mBus.advertiseName("com.test.well.known.name", SessionOpts.TRANSPORT_ANY);if (status != Status.OK) {Log.i(TAG,"advertise name on bus failed.");mBus.releaseName("com.test.well.know.name");System.exit(0);return;}elseToast.makeText(getApplicationContext(),"advertise name=com.test.well.known.name",Toast.LENGTH_SHORT).show();}static{System.loadLibrary("alljoyn_java");}
}

注意：静态初始化块中的loadlibrary不能少掉。上面的例子参照的是chat源码。

接口代码：

package com.example.siemens.testgetmethod;import org.alljoyn.bus.BusException;
import org.alljoyn.bus.annotation.BusInterface;
import org.alljoyn.bus.annotation.BusMethod;/*** Created by Siemens on 2016/4/8.*/
@BusInterface (name = "org.my.interface.name")
public interface MyInterface {
//    @BusMethod
//    void show(String test) throws BusException;
//    @BusMethod
//    int add(int a,int b) throws BusException;@BusMethodString cat(String a,String b) throws BusException;
}

注意：格式必须按照这种格式来，上面接口的name属性后面的值很重要client要对应。

client代码如下：

package com.example.siemens.testgetmethodclient;import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;import org.alljoyn.bus.BusAttachment;
import org.alljoyn.bus.BusListener;
import org.alljoyn.bus.Mutable;
import org.alljoyn.bus.ProxyBusObject;
import org.alljoyn.bus.SessionListener;
import org.alljoyn.bus.SessionOpts;
import org.alljoyn.bus.Status;public class MyService extends Service {private final String TAG="MyClientService";public MyService() {}@Overridepublic IBinder onBind(Intent intent) {// TODO: Return the communication channel to the service.
//        throw new UnsupportedOperationException("Not yet implemented");return null;}private BusAttachment mBus=null;private static final short CONTACT_PORT=42;//代理总线对象；接口对象private ProxyBusObject mProxyObj;public MyInterface mInterface;
//    public MyInterface getmInterface(){
//        return mInterface;
//    }//application对象private ClientApplication mApplication;@Overridepublic void onCreate(){mApplication=(ClientApplication)getApplication();//守护进程不能忘org.alljoyn.bus.alljoyn.DaemonInit.PrepareDaemon(getApplicationContext());  //启动守护进程mBus=new BusAttachment(getApplication().getPackageName(),BusAttachment.RemoteMessage.Receive);//连接两次？
//        Status status=mBus.connect();
//        if (Status.OK != status) {
//            Log.i(TAG,"client busattachment first connect to bus failed.");
//            System.exit(0);
//            return;
//        }mBus.registerBusListener(new BusListener(){@Overridepublic void foundAdvertisedName(String name, short transport,String namePrefix){mBus.enableConcurrentCallbacks();short contactPort = CONTACT_PORT;SessionOpts sessionOpts = new SessionOpts();sessionOpts.traffic = SessionOpts.TRAFFIC_MESSAGES;sessionOpts.isMultipoint = false;sessionOpts.proximity = SessionOpts.PROXIMITY_ANY;sessionOpts.transports = SessionOpts.TRANSPORT_ANY;Mutable.IntegerValue sessionId = new Mutable.IntegerValue();Status status = mBus.joinSession(name,contactPort,sessionId,sessionOpts,new SessionListener());mProxyObj = mBus.getProxyBusObject("com.test.well.known.name", "/myBusObject", sessionId.value, new Class[]{MyInterface.class});mInterface=mProxyObj.getInterface(MyInterface.class);//personal addmApplication.setTestInterface(mInterface);}});//连接两次？？官网API问题？？？Status status=mBus.connect();if (Status.OK != status) {Log.i(TAG,"client busattachment second connect to bus failed.");System.exit(0);return;}//找到指定名称的busAttachmentstatus = mBus.findAdvertisedName("com.test.well.known.name");if (status != Status.OK) {Log.i(TAG,"client findAdvertisedName failed.");System.exit(0);return;}elseToast.makeText(getApplicationContext(),"find name=com.test.well.known.name success.",Toast.LENGTH_SHORT).show();}static{System.loadLibrary("alljoyn_java");}
}

同时client端app也需要知道总线接口，但是要通过代理对象获得方法的具体实现，也要包含接口类，同server接口类。

总结：有4个client和server需要统一的地方。1.advertise的那个name，客户端是根据这个名称找server。2.接口类，server和client都要知道，server提供实现，client不知道具体实现。3.session设置的端口号，client的session port要和server统一。4.client要知道，server上总线对象在总线附件上注册的路径。