客户端

1. 链接服务器Socket
2. 发送消息

package com.ayv.try02;import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;//客户端
public class TcoClientDemo01 {public static void main(String[] args) {Socket socket =null;OutputStream os =   null;try {//知道服务器端口号InetAddress serverIP = InetAddress.getByName("127.0.0.1");int port=9999;//创建一个socket链接socket = new Socket(serverIP,port);//发送一个消息IO流os = socket.getOutputStream();os.write("hello world".getBytes());} catch (Exception e) {e.printStackTrace();} finally {//异常if(os!=null){try {os.close();} catch (IOException e) {e.printStackTrace();}}if(socket!=null){try {socket.close();} catch (IOException e) {e.printStackTrace();}}}}
}

服务器

1. 建立服务的端口 serverSocket
2. 等待用户的链接 accept
3. 接收用户的消息

package com.ayv.try02;import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;//服务端
public class TcpServeDemo02 {public static void main(String[] args) {ServerSocket serverSocket=null;Socket socket =null;InputStream is =null;ByteArrayOutputStream baos =null;try {                 serverSocket = new ServerSocket(9999);//等待客户端连接socket = serverSocket.accept();//读取客户端消息is = socket.getInputStream();//管道流baos = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len;while((len=is.read(buffer))!=-1){baos.write(buffer,0,len);}System.out.println(baos.toString());} catch (Exception e) {e.printStackTrace();} finally {if(baos!=null){try {baos.close();} catch (IOException e) {e.printStackTrace();}}if(is!=null){try {is.close();} catch (IOException e) {e.printStackTrace();}}if(socket!=null){try {socket.close();} catch (IOException e) {e.printStackTrace();}}if(serverSocket!=null){try {serverSocket.close();} catch (IOException e) {e.printStackTrace();}}}}
}

review：查询IP和端口

package com.ayv.try01;import java.net.InetAddress;
import java.net.UnknownHostException;
//测试IP
public class TestInetadderss {public static void main(String[] args) {//InetAddress intAddress1 = null;try {//查询本机地址InetAddress intAddress1 = InetAddress.getByName("127.0.0.1");System.out.println(intAddress1);InetAddress intAddress3 = InetAddress.getByName("localhost");System.out.println(intAddress3);InetAddress intAddress4 = InetAddress.getLocalHost();System.out.println(intAddress4);//查询网站IP地址InetAddress intAddress2 = InetAddress.getByName("www.baidu.com");System.out.println(intAddress2);} catch (UnknownHostException e) {e.printStackTrace();}}
}

发送文件

//服务端
package com.ayv.try02;import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;public class TcpServerDamo2 {public static void main(String[] args) throws Exception {//创建服务ServerSocket serverSocket = new ServerSocket(9000);//监听客户端的链接Socket socket = serverSocket.accept(); /**阻断式监听，会一直等待客户端链接*///获取输入流InputStream is = socket.getInputStream();//文件输入FileOutputStream fos = new FileOutputStream(new File("receive.jpg"));byte[] buffer = new byte[1024];int len;while((len=is.read(buffer))!=-1){fos.write(buffer,0,len);}fos.close();is.close();socket.close();serverSocket.close();}}

//客户端
package com.ayv.try02;import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;public class TCPClientDamo2 {public static void main(String[] args) throws Exception {//创建一个Socket链接Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9000);//创建一个输出流OutputStream os = socket.getOutputStream();//读取文件FileInputStream fis = new FileInputStream(new File("观望.jpg"));//写出文件byte[] buffer = new byte[1024];int len;while((len=fis.read(buffer))!=-1){os.write(buffer,0,len);}//关闭资源fis.close();os.close();socket.close();}
}