(1)HTTP是传统的请求响应式的网络通信方式,不能实现服务端主动向客户端发送消息。WebSocket可以实现服务端,客户端互发消息。
(2)WebSocket使用ws协议,HTTP使用http协议(使用的URL不同)
●相同点:服务端都能主动发消息给客户端
●不同点:1.socket基于TCP/IP协议,Websocket基于ws协议
2.Websocket只能面向链接
总结:socket更灵活,Websocket更简单
<uses-permission android:name="android.permission.INTERNET"/>
implementation "org.java-websocket:Java-WebSocket:1.5.1"
package com.example.clientapplication;
public class MessageEvent {
private String message; //网络数据内容
private int number; //网络数据分类
public MessageEvent(int number, String message) {
this.message = message;
this.number = number;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public int getNumber() {
return number;
}
public void setNumber(int number) {
this.number = number;
}
}
使用EeventBus,将收到的消息传递给主活动。
package com.example.webclienttestapplication;
import android.util.Log;
import org.greenrobot.eventbus.EventBus;
import org.java_websocket.exceptions.WebsocketNotConnectedException;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
public class WebSocketClient extends org.java_websocket.client.WebSocketClient {
public WebSocketClient(URI serverUri) {
super(serverUri);
}
@Override
public void onOpen(ServerHandshake handshakedata) {
//开启连接
Log.d("WebSocketClient","onOpen"+"成功连接到:"+getRemoteSocketAddress());
EventBus.getDefault().post(new MessageEvent(2,"onOpen:"+getRemoteSocketAddress()));
MainActivity.isClient=true;
}
@Override
public void onMessage(String message) {
//接受消息
Log.d("WebSocketClient","onMessage"+message);
EventBus.getDefault().post(new MessageEvent(1,getRemoteSocketAddress()+":"+message));
}
@Override
public void onClose(int code, String reason, boolean remote) {
//断开连接
Log.d("WebSocketClient","onClose");
EventBus.getDefault().post(new MessageEvent(2,"onClose:"+reason));
}
@Override
public void onError(Exception ex) {
//发生错误
Log.d("WebSocketClient","onError");
EventBus.getDefault().post(new MessageEvent(2,"onError:"+ex.toString()));
}
private static WebSocketClient webSocketClient;
//发起连接
public static boolean connect(String ip) {
if (webSocketClient != null) {
Release();
}
if (webSocketClient == null ) {
URI uri = URI.create("ws://"+ip+":25211");
webSocketClient = new WebSocketClient(uri);
}
try {
webSocketClient.connectBlocking();
return true;
} catch (InterruptedException e) {
e.printStackTrace();
return false;
}
}
public static void Release() {
Close();
webSocketClient = null;
}
public static void Close() {
if (webSocketClient == null) return;
if (!webSocketClient.isOpen()) return;
try {
webSocketClient.closeBlocking();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
//发送消息
public static void Send(String string) {
if (webSocketClient == null) return;
if (!webSocketClient.isOpen())
Reconnect();
try {
webSocketClient.send(string);
} catch (WebsocketNotConnectedException e) {
e.printStackTrace();
}
}
public static boolean Reconnect() {
if (webSocketClient == null) return false;
if (webSocketClient.isOpen()) return true;
try {
webSocketClient.reconnectBlocking();
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
}
package com.example.webclienttestapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import org.greenrobot.eventbus.EventBus;
import org.greenrobot.eventbus.Subscribe;
import org.greenrobot.eventbus.ThreadMode;
public class MainActivity extends AppCompatActivity {
public static boolean isClient;
private int mMessage = 10;
private StringBuffer mShowBuffer = new StringBuffer();
private StringBuffer mErrorBuffer = new StringBuffer();
private TextView mTvShow,mTvError;
private Button mBtnSend;
private static final int TV_SHOW = 1; //消息内容
private static final int TV_ERROR = 2; //异常信息
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initUi();
EventBus.getDefault().register(this); //EventBus注册
mBtnSend.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (isClient == true)
WebSocketClient.Send(mMessage++ + ""); //发送消息
else Toast.makeText(MainActivity.this, "连接失败", Toast.LENGTH_SHORT).show();
}
});
new Thread(new Runnable() {
@Override
public void run() {
WebSocketClient.connect("192.168.91.149"); // 发起连接
}
}).start();
}
@Subscribe(threadMode = ThreadMode.MAIN)
public void MessageEventBus(MessageEvent messageEvent){
switch (messageEvent.getNumber()) {
case TV_SHOW://
mShowBuffer.append(messageEvent.getMessage());
mTvShow.setText(mShowBuffer);
break;
case TV_ERROR:
mErrorBuffer.append(messageEvent.getMessage());
mTvError.setText(mErrorBuffer);
break;
}
}
private void initUi() {
mBtnSend = findViewById(R.id.btn_send);
mTvShow = findViewById(R.id.tv_show);
mTvError = findViewById(R.id.tv_error);
}
@Override
protected void onDestroy() {
super.onDestroy();
EventBus.getDefault().unregister(this); //取消注册
}
}
XML代码
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:id="@+id/tv_show"
android:layout_width="match_parent"
android:layout_height="100dp"
android:text="Hello World!"
android:textSize="23sp"
/>
<Button
android:id="@+id/btn_send"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="发送"
android:textSize="23sp"/>
<TextView
android:id="@+id/tv_error"
android:layout_marginTop="15dp"
android:layout_width="match_parent"
android:layout_height="100dp"
android:textSize="23sp"
/>
</LinearLayout>
前两步与客户端相同
package com.example.websockettestapplication;
import android.util.Log;
import org.greenrobot.eventbus.EventBus;
import org.java_websocket.WebSocket;
import org.java_websocket.handshake.ClientHandshake;
import java.net.InetSocketAddress;
public class WebSocketServer extends org.java_websocket.server.WebSocketServer{
public static WebSocketServer websocketServer;
WebSocketServer(InetSocketAddress host){
super(host);
}
public static void ready(){
InetSocketAddress myHost = new InetSocketAddress("192.168.91.149", 25211);
WebSocketServer websocketServer = new WebSocketServer(myHost);
try {
websocketServer.start();
} catch (Exception e) {
e.printStackTrace();
}
WebSocketServer.websocketServer = websocketServer;
}
public static void Stop() {
try {
websocketServer.stop();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void Send(String string) {
try {
websocketServer.broadcast(string);
//websocketServer.broadcast(string,clients);//Collection<WebSocket> clients,指定发送到哪个客户端
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onOpen(WebSocket conn, ClientHandshake handshake) {
Log.d("WebSocketServer","onOpen():连接到: "+getRemoteSocketAddress(conn));
EventBus.getDefault().post(new MessageEvent(1,"onOpen:"+getRemoteSocketAddress(conn)));
MainActivity.isServer=true;
}
@Override
public void onClose(WebSocket conn, int code, String reason, boolean remote) {
Log.d("WebSocketServer","onClose");
EventBus.getDefault().post(new MessageEvent(2,"onClose:"+reason));
websocketServer = null;
}
@Override
public void onMessage(WebSocket conn, String message) {
Log.d("WebSocketServer","onMessage"+message);
EventBus.getDefault().post(new MessageEvent(1,message));
}
@Override
public void onError(WebSocket conn, Exception ex) {
Log.d("WebSocketServer","onError"+ex.toString());
EventBus.getDefault().post(new MessageEvent(2,"onError:"+ex.toString()));
}
@Override
public void onStart() {
Log.d("WebSocketServer","onStart:"+websocketServer.getAddress().getHostName());
EventBus.getDefault().post(new MessageEvent(2,"onStart:服务器已就绪"+websocketServer.getAddress().getHostName()));
}
}
package com.example.websockettestapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import org.greenrobot.eventbus.EventBus;
import org.greenrobot.eventbus.Subscribe;
import org.greenrobot.eventbus.ThreadMode;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
import java.util.Date;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class MainActivity extends AppCompatActivity {
public static boolean isServer;
private int mMessage = 0;
private StringBuffer mShowBuffer = new StringBuffer();
private StringBuffer mErrorBuffer = new StringBuffer();
private TextView mTvShow,mTvError;
private Button mBtnSend;
private static final int TV_SHOW = 1;
private static final int TV_ERROR = 2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initUi();
EventBus.getDefault().register(this);
mBtnSend.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (isServer == true)
WebSocketServer.Send("1111122222");
else Toast.makeText(MainActivity.this, "连接失败", Toast.LENGTH_SHORT).show();
}
});
ExecutorService fixedThreadPool = Executors.newFixedThreadPool(10);
fixedThreadPool.execute(new Runnable() {
@Override
public void run() {
WebSocketServer.ready();
}
});
}
@Subscribe(threadMode = ThreadMode.MAIN)
public void MessageEventBusa(MessageEvent messageEvent){
switch (messageEvent.getNumber()) {
case TV_SHOW://
mShowBuffer.append(messageEvent.getMessage());
mTvShow.setText(mShowBuffer);
break;
case TV_ERROR:
mErrorBuffer.append(messageEvent.getMessage());
mTvError.setText(mErrorBuffer);
break;
}
}
private void initUi() {
mBtnSend = findViewById(R.id.btn_send);
mTvShow = findViewById(R.id.tv_show);
mTvError = findViewById(R.id.tv_error );
}
@Override
protected void onDestroy() {
super.onDestroy();
EventBus.getDefault().unregister(this);
}
}
XML代码
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:id="@+id/tv_show"
android:layout_width="match_parent"
android:layout_height="100dp"
android:text="Hello World!"
android:textSize="23sp"
/>
<Button
android:id="@+id/btn_send"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="发送"
android:textSize="23sp"/>
<TextView
android:id="@+id/tv_error"
android:layout_marginTop="15dp"
android:layout_width="match_parent"
android:layout_height="100dp"
android:textSize="23sp"
/>
</LinearLayout>
| 2 | Android Studio 2021.2.1 Patch1 | 开发工具 |
| 3 | Gradle Version | 7.3.3 |
| 4 | Android Gradle Plugin Version | 7.2.1 |
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