Java高级部分总结

Dear 丶 2023-07-21 13:25 30阅读 0赞

## 网络编程（Socket编程） ##

1.网络通信要素：

> IP和端口号;  
> 网络通信协议

//表示互联网协议 (IP) 地址
    	public static void main(String[] args) {
        
            try {
        
                InetAddress inetAddress = InetAddress.getByName("www.baidu.com");
                //www.baidu.com/182.61.200.6
                System.out.println(inetAddress);
                //www.baidu.com
                System.out.println(InetAddress.getHostName());
                //182.61.200.6
                System.out.println(InetAddress.getHostAddress());
            } catch (UnknownHostException e) {
        
                e.printStackTrace();
            }
        }
    
    	//端口号16位（0~65535）

> 端口号和IP组合得出一个网络套接字Socket

@Test
        public void client(){
        
            Socket socket = null;
            OutputStream outputStream = null;
            try {
        
                InetAddress inetAddress = InetAddress.getByName("127.0.0.1");
                socket = new Socket(inetAddress,3388);
                outputStream = socket.getOutputStream();
                outputStream.write("我爱你中国".getBytes());
                outputStream.close();
                socket.close();
            } catch (IOException e) {
        
                e.printStackTrace();
            } finally {
        
                try {
        
                    if(outputStream!= null){
        
                        outputStream.close();
                    }
                } catch (IOException e) {
        
                    e.printStackTrace();
                }
                try {
        
                    if(socket != null){
        
                        socket.close();
                    }
                } catch (IOException e) {
        
                    e.printStackTrace();
                }
            }
        }
    
        @Test
        public void server(){
        
            ServerSocket serverSocket = null;
            Socket socket = null;
            InputStream inputStream = null;
            ByteArrayOutputStream byteArrayOutputStream = null;
            try {
        
                serverSocket = new ServerSocket(3388);
                socket = serverSocket.accept();
                inputStream = socket.getInputStream();
    
                byteArrayOutputStream = new ByteArrayOutputStream();
                byte[] bytes = new byte[5];
                int len;
                while ((len = inputStream.read(bytes)) != -1){
        
                    byteArrayOutputStream.write(bytes,0,len);
                }
    
                System.out.println(byteArrayOutputStream.toString());
            } catch (IOException e) {
        
                e.printStackTrace();
            } finally {
        
                if(byteArrayOutputStream != null){
        
                    try {
        
                        byteArrayOutputStream.close();
                    } catch (IOException e) {
        
                        e.printStackTrace();
                    }
                }
                if(inputStream != null){
        
                    try {
        
                        inputStream.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();
                    }
                }
            }
        }

@Test
        public void client() {
        
            Socket socket = null;
            OutputStream outputStream = null;
            FileInputStream fileInputStream = null;
            try {
        
                socket = new Socket(InetAddress.getByName("127.0.0.1"), 8809);
                outputStream = socket.getOutputStream();
                fileInputStream = new FileInputStream(new File("Screenshot.png"));
                byte[] bytes = new byte[1024];
                int len;
                while ((len = fileInputStream.read(bytes)) != -1) {
        
                    outputStream.write(bytes, 0, len);
                }
            } catch (IOException e) {
        
                e.printStackTrace();
            } finally {
        
                if (fileInputStream != null) {
        
                    try {
        
                        fileInputStream.close();
                    } catch (IOException e) {
        
                        e.printStackTrace();
                    }
                } else if (outputStream != null) {
        
                    try {
        
                        outputStream.close();
                    } catch (IOException e) {
        
                        e.printStackTrace();
                    }
                } else if (socket != null) {
        
                    try {
        
                        socket.close();
                    } catch (IOException e) {
        
                        e.printStackTrace();
                    }
                }
            }
        }
    
        @Test
        public void server() {
        
            ServerSocket serverSocket = null;
            Socket socket = null;
            InputStream inputStream = null;
            FileOutputStream fileOutputStream = null;
            try {
        
                serverSocket = new ServerSocket(8809);
                socket = serverSocket.accept();
                inputStream = socket.getInputStream();
                fileOutputStream = new FileOutputStream(new File("shot.png"));
                byte[] bytes = new byte[1024];
                int len;
                while ((len = inputStream.read(bytes)) != -1) {
        
                    fileOutputStream.write(bytes, 0, len);
                }
            } catch (IOException e) {
        
                e.printStackTrace();
            } finally {
        
                if (fileOutputStream != null) {
        
                    try {
        
                        fileOutputStream.close();
                    } catch (IOException e) {
        
                        e.printStackTrace();
                    }
                }
                if (inputStream != null) {
        
                    try {
        
                        inputStream.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();
                    }
                }
            }
        }