java socket网络编程

一、socket

　　服务端

public class A01server {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(8888);
        Socket socket = serverSocket.accept();

        InputStream inputStream = socket.getInputStream();
        byte[] bytes = new byte[1024];
        int len = inputStream.read(bytes);
        System.out.println(new String(bytes, 0, len));


        OutputStream outputStream = socket.getOutputStream();
        outputStream.write("收到谢谢".getBytes());

        socket.close();
        serverSocket.close();
    }
}

　　客户端

public class A01client {
    public static void main(String[] args) throws IOException {
        Socket socket = new Socket("127.0.0.1", 8888);

        OutputStream outputStream = socket.getOutputStream();
        outputStream.write("你好服务器".getBytes());

        InputStream inputStream = socket.getInputStream();
        byte[] bytes = new byte[1024];
        int len = inputStream.read(bytes);
        System.out.println(new String(bytes, 0, len));

        socket.close();
    }
}

二、socket文件上传案例

　　服务端

public class A02fileserver {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(8888);

        while (true) {
            Socket socket = serverSocket.accept();
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        InputStream inputStream = socket.getInputStream();
                        File file = new File("upload");
                        if (!file.exists()) {
                            file.mkdirs();
                        }
                        FileOutputStream fileOutputStream = new FileOutputStream(file + "\" + System.currentTimeMillis() + ".txt");

                        byte[] bytes = new byte[1024];
                        int len = 0;
                        while ((len = inputStream.read(bytes)) != -1) {
                            fileOutputStream.write(bytes, 0, len);
                        }

                        socket.getOutputStream().write("上传成功".getBytes());

                        fileOutputStream.close();
                        socket.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();
        }
    }
}

　　客户端

public class A02fileclient {
    public static void main(String[] args) throws IOException {
        FileInputStream fileInputStream = new FileInputStream("data.txt");
        Socket socket = new Socket("127.0.0.1", 8888);
        OutputStream outputStream = socket.getOutputStream();

        byte[] bytes = new byte[1024];
        int len = 0;
        while ((len = fileInputStream.read(bytes)) != -1) {
            outputStream.write(bytes, 0, len);
        }

        socket.shutdownOutput();//输出流结束标记

        InputStream inputStream = socket.getInputStream();
        while ((len = inputStream.read(bytes)) != -1) {
            System.out.println(new String(bytes, 0, len));
        }

        fileInputStream.close();
        socket.close();
    }
}

三、模拟BS服务器

public class A03browserserver {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(8080);

        while (true) {
            Socket socket = serverSocket.accept();
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        InputStream inputStream = socket.getInputStream();
                        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                        String line = bufferedReader.readLine();
                        String[] arr = line.split(" ");
                        String htmlpath = arr[1].substring(1);
                        System.out.println(htmlpath);

                        FileInputStream fileInputStream = new FileInputStream(htmlpath);
                        OutputStream outputStream = socket.getOutputStream();
                        outputStream.write("HTTP/1.1 200 OK
".getBytes());
                        outputStream.write("Content-Type:text/html
".getBytes());
                        outputStream.write("
".getBytes());

                        byte[] bytes = new byte[1024];
                        int len = 0;
                        while ((len = fileInputStream.read(bytes)) != -1) {
                            outputStream.write(bytes, 0, len);
                        }

                        fileInputStream.close();
                        socket.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();
        }
    }
}

注意：输入流如果未读到输出流的结束标记，输入流就会处于阻塞状态。