【Android】使用Socket实现跨设备通讯
1 Socket 简介
Socket（套接字）是应用层与 TCP/IP 协议通信的中间软件抽象层，它是一组接口，用户只需面向 Socket 编程，即可实现跨设备（网络）通讯。
Socket 是 java 里的东西，不是 Android 特有的，使用 Socket 需要导入的类如下。
java.net.ServerSocket
java.net.Socket
（1）服务端主要接口调用
// 获取 socket
mServerSocket = new ServerSocket(port)
// port 为端口号，取值：0~65535间的整数，前1024个端口号为固定端口，一般不提供给程序员使用，之后为注册端口，为避免端口冲突，建议 port 值取大点
mSocket = mServerSocket.accept() //调用此方法会阻塞线程，建议在子线程中执行
// 读取对端数据
in = mSocket.getInputStream()
byte[] bt = new byte[50]
in.read(bt)
// 向对端发送数据
out = new PrintWriter(mSocket.getOutputStream())
out.print(content)
out.flush()
（2）客户端主要接口调用
// 获取 socket
mSocket = new Socket(ip, port) //调用此方法会阻塞线程，建议在子线程中执行
// ip 为服务端设备 ip 地址
// port 为端口号，取值：0~65535间的整数，前1024个端口号为固定端口，一般不提供给程序员使用，之后为注册端口，为避免端口冲突，建议 port 值取大点
// 读取对端数据
in = mSocket.getInputStream()
byte[] bt = new byte[50]
in.read(bt)
// 向对端发送数据
out = new PrintWriter(mSocket.getOutputStream())
out.print(content)
out.flush()
本文全部代码见→使用Socket实现跨设备通讯
2 项目结构
注意：2个设备必须在局域网中（连同一个wifi ）
3 服务端（socket_S）
Server.java
package com.zhyan8.socket_s;
import android.os.Handler;
import android.os.Message;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class Server{
private ServerSocket mServerSocket;
private Socket mSocket;
private Handler mHandler;
private InputStream in;
private PrintWriter out;
private Object lock = new Object();
public Server(Handler handler, int port){
mHandler = handler;
try {
mServerSocket = new ServerSocket(port);
} catch (IOException e) {
e.printStackTrace();
}
}
public void connect() {
new Thread() {
@Override
public void run() {
try {
synchronized (lock) {
if (mSocket!=null) {
return;
}
mSocket = mServerSocket.accept();
in = mSocket.getInputStream();
out = new PrintWriter(mSocket.getOutputStream());
}
} catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}
public void begin_listen() {
while (mSocket==null) {
connect();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
new Thread() {
@Override
public void run() {
try {
while (!mSocket.isClosed()) {
byte[] bt = new byte[50];
in.read(bt);
String content = new String (bt, "UTF-8" );
if (content!=null && !content.equals("")) {
Message msg = new Message();
msg.obj = content;
mHandler.sendMessage(msg);
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}
public void send_msg(final String content) {
new Thread() {
@Override
public void run() {
out.print(content);
out.flush ();
}
}.start();
}
}
MainActivity.java
package com.zhyan8.socket_s;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private Server mServer;
private EditText et_msg;
private Button btn_send;
private TextView tv_msg;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
private void init() {
et_msg = (EditText) findViewById(R.id.et_msg);
btn_send = (Button) findViewById(R.id.btn_send);
tv_msg = (TextView) findViewById(R.id.tv_msg);
btn_send.setOnClickListener(cl);
mServer = new Server(mHandler, 1111);
mServer.begin_listen();
}
private View.OnClickListener cl = new View.OnClickListener() {
@Override
public void onClick(View v) {
String content = et_msg.getText().toString().trim();
if (content!=null && !content.equals("")) {
mServer.send_msg(content);
}
}
};
private Handler mHandler = new Handler(){
@Override
public void handleMessage(Message msg) {
String content = (String) msg.obj;
tv_msg.setText(content);
}
};
}
activity_main.xml
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:orientation="vertical" tools:context="com.zhyan8.socket_s.MainActivity"> android:layout_width="match_parent" android:layout_height="100dp" android:orientation="horizontal" android:gravity="center_vertical"> android:layout_width="wrap_content" android:layout_height="match_parent" android:text="接收的消息：" android:textSize="20sp" android:gravity="center_vertical"/> android:id="@+id/tv_msg" android:layout_width="match_parent" android:layout_height="match_parent" android:textSize="20sp" android:gravity="center_vertical"/>
android:id="@+id/et_msg" android:layout_width="match_parent" android:layout_height="100dp" android:textSize="30sp" android:background="#ffcc66"/> android:id="@+id/btn_send" android:layout_width="match_parent" android:layout_height="80dp" android:text="发送" android:textSize="30sp" android:layout_marginTop="30dp"/> 界面如下： 在 AndroidManifest.xml 文件的 manifest 标签下（与 application 同级）添加如下权限： 4 客户端（socket_C） Client.java package com.zhyan8.socket_c; import android.os.Handler; import android.os.Message; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.net.Socket; public class Client{ private Socket mSocket; private Handler mHandler; private InputStream in; private PrintWriter out; private String ip; private int port; private Object lock = new Object(); Client(Handler handler, String ip, int port) { mHandler = handler; this.ip = ip; this.port = port; } private void connect() { new Thread() { @Override public void run() { try { synchronized (lock) { if (mSocket!=null) { return; } mSocket = new Socket(ip, port); in = mSocket.getInputStream(); out = new PrintWriter(mSocket.getOutputStream()); } } catch (IOException e) { e.printStackTrace(); } } }.start(); } public void begin_listen() { while (mSocket==null) { connect(); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } new Thread() { @Override public void run() { try { while (!mSocket.isClosed()){ byte[] bt = new byte[50]; in.read(bt); String content = new String (bt, "UTF-8" ); if (content!=null && !content.equals("")) { Message msg = new Message(); msg.obj = content; mHandler.sendMessage(msg); } } } catch (IOException e) { e.printStackTrace(); } } }.start(); } public void send_msg(final String content) { new Thread() { @Override public void run() { out.print(content); out.flush(); } }.start(); } } MainActivity.java package com.zhyan8.socket_c; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.v7.app.AppCompatActivity; import android.util.Log; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; public class MainActivity extends AppCompatActivity { private Client mClient; private EditText et_msg; private Button btn_send; private TextView tv_msg; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); init(); } private void init() { et_msg = (EditText) findViewById(R.id.et_msg); btn_send = (Button) findViewById(R.id.btn_send); tv_msg = (TextView) findViewById(R.id.tv_msg); btn_send.setOnClickListener(cl); mClient = new Client(mHandler, "192.168.0.104", 1111); mClient.begin_listen(); } private View.OnClickListener cl = new View.OnClickListener() { @Override public void onClick(View v) { String content = et_msg.getText().toString().trim(); if (content!=null && !content.equals("")) { mClient.send_msg(content); } } }; private Handler mHandler = new Handler(){ @Override public void handleMessage(Message msg) { String content = (String) msg.obj; tv_msg.setText(content); } }; } activity_main.xml 同第3节。 在 AndroidManifest.xml 文件的 manifest 标签下（与 application 同级）添加如下权限： 5 效果展示 客户端： 服务端： 声明：本文转自【Android】使用Socket实现跨设备通讯