一、添加权限
<uses-permission android:name="android.permission.INTERNET" />
二、输入输出流
客户端和服务器端的输入输出流的问题容易搞混淆：如下图
在客户端：
socket.getInputStream();从socket读来自服务器的数据
socket.getOutputStream();向socket中写数据，传给服务器，服务器在它的socket的输入流读这个数据
在服务器端：
socket.getInputStream();从socket读来自客户端的数据
socket.getOutputStream();向socket中写数据，传给客户端，客户端在它的socket的输入流读这个数据
就是说客户端和服务器端的输入输出流是对应的，输入流连接到输出流
输入输出流的包装：
方法一：数据二进制流
DataInputStream in=new DataInputStream(socket.getInputStream());//接收客户端信息 DataOutputStream out=new DataOutputStream(socket.getOutputStream()); //向客户端发送消息
方法二：
PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true); BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
三、客户端/服务器端实现
创建服务器端的步骤：
1，指定端口实例化一个ServerSocket
2,调用ServerSocket的accept方法等待连接期间阻塞
3，获取位于底层的Socket流进行读写操作
4，将数据封装成流
5，对Socket进行读写
6，关闭流
创建客户端的步骤：
1，通过IP地址和端口实例化Socket，请求连接服务器
2，获取位于底层的Socket流进行读写操作
3，将数据封装成流（BufferedReader/PrintWriter,DataOutputStream/DataInputStream）的实例
4，对Socket进行读写
5，关闭流
socketClient,java
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class socketClient extends Activity {
private Button button;
private TextView text;
private EditText edit;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button) findViewById(R.id.button);
edit = (EditText) findViewById(R.id.edit);
text = (TextView) findViewById(R.id.text);
button.setOnClickListener(new View.OnClickListener() {
private Socket socket = null;
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
String sendMsg = edit.getText().toString() + "\r\n";
try {
socket = new Socket("192.168.0.37", 8888); // 创建Socket，其中ip地址为我的PC机器的地址，手机通过wifi上网和服务器在一个网段
// PrintWriter out = new PrintWriter(new BufferedWriter(new
// OutputStreamWriter(socket.getOutputStream())),true);
// out.println(sendMsg);
//
// BufferedReader in = new BufferedReader(new
// InputStreamReader(socket.getInputStream()));
// String readMsg = in.readLine();
// if(readMsg !=null){
// text.setText(readMsg);
// }else{
// text.setText("错误");
// }
//
// out.close();
// in.close();
// socket.close();
DataOutputStream out = new DataOutputStream(socket
.getOutputStream()); // 向服务器发送消息
out.writeUTF(sendMsg);
out.flush();
DataInputStream in = new DataInputStream(socket
.getInputStream()); // 接收来自服务器的消息
String readMsg = in.readUTF();
if (readMsg != null) {
text.setText(readMsg);
}
out.close();
in.close();
socket.close();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}
Server.java
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
public Server(){
new ServerThread().start();
}
class ServerThread extends Thread{
public void run() {
try {
ServerSocket ss=new ServerSocket(8888); ////创建一个ServerSocket对象，并让这个ServerSocket在8888端口监听
while(true){
Socket socket=ss.accept(); //调用ServerSocket的accept()方法，接受客户端所发送的请求，如果客户端没有发送数据，那么该线程就停滞不继续
// try {
// BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream())); //接收客户端信息
// String readline = in.readLine();
// System.out.println("readline:"+readline);
//
// PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
// out.println("link server success");
//
// in.close(); //关闭流
// out.close();//关闭流
// socket.close();//关闭打开的socket
//
// } catch (Exception e) {
// // TODO: handle exception
// }finally{
// // socket.close();//
// }
try {
DataInputStream in=new DataInputStream(socket.getInputStream());//接收客户端信息
String readline=in.readUTF();
System.out.println(readline);
DataOutputStream out=new DataOutputStream(socket.getOutputStream()); //向客户端发送消息
out.writeUTF("link server success");
out.flush();
in.close(); //关闭流
out.close();//关闭流
socket.close();//关闭打开的socket
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
} catch (IOException e) {
System.out.println(e.getMessage());
}
}
}
public static void main(String[] args) throws IOException {
new Server(); //开启服务器
}
}
