一、使用tcp協議實現client向server發送數據

//TCP編程例一：客戶端給服務端發送信息。服務端輸出此信息到控制臺上//網絡編程實際上就是Socket的編程public class TestTCP1 {	// 客戶端	@Test	public void client() {		Socket socket = null;		OutputStream os = null;		try {			// 1.創建一個Socket的對象，通過構造器指明服務端的ip地址，以及其接收程序的端口號			socket = new Socket(InetAddress.getByName("127.0.0.1"), 9090);			// 2.getOutputStream()：發送數據，方法返回OutputStream的對象			os = socket.getOutputStream();			// 3.具體的輸出過程			os.write("我是客戶端，請多關照".getBytes());		} catch (IOException e) {			// TODO Auto-generated catch block			e.PRintStackTrace();		} finally {			// 4.關閉相應的流和Socket對象			if (os != null) {				try {					os.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}			if (socket != null) {				try {					socket.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}		}	}	// 服務端	@Test	public void server() {		ServerSocket ss = null;		Socket s = null;		InputStream is = null;		try {			// 1.創建一個ServerSocket的對象，通過構造器指明自身的端口號			ss = new ServerSocket(9090);			// 2.調用其accept()方法，返回一個Socket的對象			s = ss.accept();			// 3.調用Socket對象的getInputStream()獲取一個從客戶端發送過來的輸入流			is = s.getInputStream();			// 4.對獲取的輸入流進行的操作			byte[] b = new byte[20];			int len;			while ((len = is.read(b)) != -1) {				String str = new String(b, 0, len);				System.out.print(str);			}			System.out.println("收到來自于" + s.getInetAddress().getHostAddress()					+ "的連接");		} catch (IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} finally {			// 5.關閉相應的流以及Socket、ServerSocket的對象			if (is != null) {				try {					is.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}			if (s != null) {				try {					s.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}			if (ss != null) {				try {					ss.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}		}	}}二、在一的基礎上實現server向client返回數據
//TCP編程例二：客戶端給服務端發送信息，服務端將信息打印到控制臺上，同時發送“已收到信息”給客戶端public class TestTCP2 {	//客戶端	@Test	public void client(){		Socket socket = null;		OutputStream os = null;		InputStream is = null;		try {			socket = new Socket(InetAddress.getByName("127.0.0.1"),8989);			os = socket.getOutputStream();			os.write("我是客戶端".getBytes());			//shutdownOutput():執行此方法，顯式的告訴服務端發送完畢！			socket.shutdownOutput();			is = socket.getInputStream();			byte[] b = new byte[20];			int len;			while((len = is.read(b)) != -1){				String str = new String(b,0,len);				System.out.print(str);			}		} catch (IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}finally{			if(is != null){				try {					is.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}			if(os != null){				try {					os.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}			if(socket != null){				try {					socket.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}		}					}	//服務端	@Test	public void server(){		ServerSocket ss = null;		Socket s = null;		InputStream is = null;		OutputStream os = null;		try {			ss = new ServerSocket(8989);			s = ss.accept();			is = s.getInputStream();			byte[] b = new byte[20];			int len;			while((len = is.read(b)) != -1){				String str = new String(b,0,len);				System.out.print(str);			}			os = s.getOutputStream();			os.write("我已收到你的情意".getBytes());					} catch (IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}finally{			if(os != null){				try {					os.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}			if(is != null){				try {					is.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}			if(s != null){				try {					s.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}			if(ss != null){				try {					ss.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}							}		}			}}三、使用流，client向server發送文件
//TCP編程例三：從客戶端發送文件給服務端，服務端保存到本地。并返回“發送成功”給客戶端。并關閉相應的連接。//如下的程序，處理異常時，要使用try-catch-finally!!本例僅為了書寫方便~public class TestTCP3 {	@Test	public void client()throws Exception{		//1.創建Socket的對象		Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9898);		//2.從本地獲取一個文件發送給服務端		OutputStream os = socket.getOutputStream();		FileInputStream fis = new FileInputStream(new File("1.jpg"));		byte[] b = new byte[1024];		int len;		while((len = fis.read(b)) != -1){			os.write(b,0,len);		}		socket.shutdownOutput();		//3.接收來自于服務端的信息		InputStream is = socket.getInputStream();		byte[] b1 = new byte[1024];		int len1;		while((len1 = is.read(b1)) != -1){			String str = new String(b1,0,len1);			System.out.print(str);		}		//4.關閉相應的流和Socket對象		is.close();		os.close();		fis.close();		socket.close();	}	@Test	public void server() throws Exception{		//1.創建一個ServerSocket的對象		ServerSocket ss = new ServerSocket(9898);		//2.調用其accept()方法，返回一個Socket的對象		Socket s = ss.accept();		//3.將從客戶端發送來的信息保存到本地		InputStream is = s.getInputStream();		FileOutputStream fos = new FileOutputStream(new File("3.jpg"));		byte[] b = new byte[1024];		int len;		while((len = is.read(b)) != -1){			fos.write(b, 0, len);		}		System.out.println("收到來自于" + s.getInetAddress().getHostAddress() + "的文件");		//4.發送"接收成功"的信息反饋給客戶端		OutputStream os = s.getOutputStream();		os.write("你發送的圖片我已接收成功！".getBytes());		//5.關閉相應的流和Socket及ServerSocket的對象		os.close();		fos.close();		is.close();		s.close();		ss.close();	}}