通过Socket传送文件的例子

一、表示Socket服务端的类：Server.java

public class Server extends Thread{
	public static int port = 6789;
	public static String host = "10.60.1.127";
	private static ServerSocket server = null;
	
	public void run() {
		if(server == null){
			try{
				//1、新建ServerSocket实例
				server = new ServerSocket(port);
			}catch(IOException e){
				e.printStackTrace();
			}
		}
		
		System.out.println("服务器启动...");
		while(true){
			try{
				//2、访问ServerSocket实例的accept方法取得一个客户端Socket对象
				Socket client = server.accept();
				if(client == null) continue;
				
				new SocketConnection(client, "D:\\").start();
				
			}catch(IOException ex){
				ex.printStackTrace();
			}
		}
	}

	public static void main(String[] args) {
		new Server().start();
	}
	
}

Socket客户端处理类：SocketConnection.java

public class SocketConnection extends Thread{
	private Socket client;
	private String filepath;
	
	public SocketConnection(Socket client, String filepath){
		this.client = client;
		this.filepath = filepath;
	}
	
	public void run(){
		if(client == null) return;
		
		DataInputStream in = null;
		DataOutputStream writer = null;
		
		try{
			//3、访问Socket对象的getInputStream方法取得客户端发送过来的数据流
			in = new DataInputStream(new BufferedInputStream(client.getInputStream()));
			
			String fileName = in.readUTF(); //取得附带的文件名
			
			if(filepath.endsWith("/") == false && filepath.endsWith("\\") == false){
				filepath += "\\";
			}
			filepath += fileName;
			
			//4、将数据流写到文件中
			writer = new DataOutputStream(new BufferedOutputStream(new BufferedOutputStream(new FileOutputStream(new File(filepath)))));
			
			int bufferSize = 2048;
            byte[] buf = new byte[bufferSize];
            
			int read = 0;
			while((read=in.read(buf)) != -1){
				writer.write(buf, 0, read);
			}
			
			writer.flush();
			System.out.println("数据接收完毕");
			
		}catch(IOException ex){
			ex.printStackTrace();
		}finally{
			try{
				in.close();
				writer.close();
				client.close();
			}catch(IOException e){
				e.printStackTrace();
			}
		}
		
	}
	
}

二、表示客户端的类：Client.java

public class Client {
	private Socket client;
	private boolean connected;
	
	public boolean isConnected() {
		return connected;
	}

	public void setConnected(boolean connected) {
		this.connected = connected;
	}

	public Client(String host, int port){
		try {
			//1、新建Socket对象
			client = new Socket(host, port);
			System.out.println("服务器连接成功！");
			
			this.connected = true;
			
		} catch (UnknownHostException e) {
			this.connected = false;
			close();
		} catch (IOException e) {
			System.out.println("服务器连接失败！");
			this.connected = false;
			close();
		}
	}
	
	/**
	 * 将文件内容发送出去
	 * 
	 * @param filepath 文件的全路径名
	 */
	public void sendFile(String filepath){
		DataOutputStream out = null;
		DataInputStream reader = null;
		try{
			if(client == null) return;

			File file = new File(filepath);
			reader = new DataInputStream(new BufferedInputStream(new FileInputStream(file)));
			
			//2、将文件内容写到Socket的输出流中
			out = new DataOutputStream(client.getOutputStream());
			
			out.writeUTF(file.getName()); //附带文件名
			
			int bufferSize = 2048; //2K
            byte[] buf = new byte[bufferSize];
            
			int read = 0;
			while((read=reader.read(buf)) != -1){
				out.write(buf, 0, read);
			}
			
			out.flush();
			
		}catch(IOException ex){
			ex.printStackTrace();
			close();
		}finally{
			try {
				reader.close();
				out.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
	
	/**
	 * 关闭Socket
	 */
	public void close(){
		if(client != null){
			try {
				client.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
	
	public static void main(String[] args) {
		Client client = new Client(Server.host, Server.port);
		if(client.isConnected()){
			client.sendFile("E:\\EKI.txt");
			client.close();
		}
	}
	
}