Java高级知识复习----Socket网络编程TCP、UDP和URL

1.TCP网络编程

1.客户端发送内容给服务器服务器将内容打印到控制台上。

package top.oneluckyguy.socket;

import org.junit.Test;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @author Liu Qingfeng
 * @create 2020-12-21----1:23
 * 实现：
 * 客户端发送内容给服务器服务器将内容打印到控制台上。
 */
public class TCPTest {
    public static void main(String[] args) {

    }
    @Test
    public void client(){
        Socket socket = null;
        OutputStream outputStream = null;
        try {
            //1.创建Socket对象，指明服务器端的ip和端口号
            InetAddress inetAddress = InetAddress.getByName("127.0.0.1");
            socket = new Socket(inetAddress,8899);
            //2.获取一个输出流用于输出数据
            outputStream = socket.getOutputStream();
            outputStream.write("你好，我是客户端".getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //3.关闭流
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (socket != null){
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }


    }
    @Test
    public void server() {
        Socket socket = null;
        InputStream inputStream = null;
        ByteArrayOutputStream byteArrayOutputStream = null;
        ServerSocket serverSocket = null;
        try {
            //1.指明自己的端口号
            serverSocket = new ServerSocket(8899);
            //2.调用accept()表示接受来自客户端的socket
            socket = serverSocket.accept();
            //3.获取输入流
            inputStream = socket.getInputStream();
//            不建议这样写字节流和中文可能会乱码
//            byte[] buffer = new byte[1024];
//            int len;
//            while((len = inputStream.read()) != -1){
//                String str = new String(buffer,0,len );
//                System.out.println(str);
//            }
            //4.读取输入流数据
            byteArrayOutputStream = new ByteArrayOutputStream();
            byte[] buffer = new byte[5];
            int len;
            //read()函数含参
            while((len = inputStream.read(buffer)) != -1){
                byteArrayOutputStream.write(buffer,0,len);
            }
            System.out.println(byteArrayOutputStream.toString());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭流
            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();
                }
            }
        }
    }
}

2.TCP Socket编程实现文件的传输

package top.oneluckyguy.socket;

import org.junit.Test;

import java.io.*;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @author Liu Qingfeng
 * @create 2020-12-21----2:07
 * TCP Socket编程
 * 从客户端发送文件给服务端，服务端保存到本地
 */
public class TCPFileTest {
    public static void main(String[] args) {

    }
    @Test
    public void client(){
        Socket socket = null;
        OutputStream outputStream = null;
        FileInputStream fileInputStream = null;
        try {
            //1.创建Socket类的对象
            socket = new Socket(InetAddress.getByName("127.0.0.1"),8899);
            //2.创建输出流
            outputStream = socket.getOutputStream();
            //3.创建输入流
            fileInputStream = new FileInputStream(new File("2.png"));
            //4.读取并输出过程
            byte[] buffer = new byte[1024];
            int len;
            while((len = fileInputStream.read(buffer)) != -1){
                outputStream.write(buffer,0,len);

            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭流
            if (fileInputStream != null){
                try {
                    fileInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            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 {
            //1.造一个ServerSocket对象
            serverSocket = new ServerSocket(8899);
            //2.获取客户端socket
            socket = serverSocket.accept();
            //3.获取输入端输入流
            inputStream = socket.getInputStream();
            //4.建立本地的存储文件
            fileOutputStream = new FileOutputStream(new File("11.png"));
            //5.获取字节过程
            byte[] buffer = new byte[1024];
            int len;
            while((len = inputStream.read(buffer)) != -1){
                fileOutputStream.write(buffer,0,len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //6.关闭流
            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();
                }
            }
        }
    }
}

3.在2的基础上服务器反馈给客户端信息

package top.oneluckyguy.socket;

import org.junit.Test;

import java.io.*;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @author Liu Qingfeng
 * @create 2020-12-21----2:07
 * TCP Socket编程
 * 从客户端发送文件给服务端，服务端保存到本地，服务器反馈给客户端信息。
 *  socket.shutdownOutput();函数用来关闭数据的输出，
 *  如果不加强制关闭函数，服务器和客户端会不知道什么时候停止输出数据，会一直处于while循环中，可以发送文件接受文件成功，但是服务器
 *  到客户端的反馈信息不会执行(因为反馈信息在while循环的后面，)
 * 
 */
public class TCPFeedback {
    public static void main(String[] args) {

    }
    @Test
    public void client(){
        Socket socket = null;
        OutputStream outputStream = null;
        FileInputStream fileInputStream = null;
        InputStream inputStream = null;
        ByteArrayOutputStream byteArrayOutputStream = null;
        try {
            //1.创建Socket类的对象
            socket = new Socket(InetAddress.getByName("127.0.0.1"),55599);
            //2.创建输出流
            outputStream = socket.getOutputStream();
            //3.创建输入流
            fileInputStream = new FileInputStream(new File("2.png"));
            //4.读取并输出过程
            byte[] buffer = new byte[1024];
            int len;
            while((len = fileInputStream.read(buffer)) != -1){
                outputStream.write(buffer,0,len);
            }
            //关闭数据的输出
            socket.shutdownOutput();
            //4.4 接受来自服务器端的反馈，并显示到控制台。
             inputStream = socket.getInputStream();
             byteArrayOutputStream = new ByteArrayOutputStream();
            Byte[] bytes = new Byte[5];
            int length;
            while((length = inputStream.read(buffer)) != -1){
                byteArrayOutputStream.write(buffer,0,length);
            }
            System.out.println(byteArrayOutputStream.toString());


        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭流
            if (fileInputStream != null){
                try {
                    fileInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (socket != null){
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (inputStream != null){
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (byteArrayOutputStream != null){
                try {
                    byteArrayOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
    @Test
    public void server() {
        ServerSocket serverSocket = null;
        Socket socket = null;
        InputStream inputStream = null;
        FileOutputStream fileOutputStream = null;
        OutputStream outputStream = null;
        try {
            //1.造一个ServerSocket对象
            serverSocket = new ServerSocket(55599);
            //2.获取客户端socket
            socket = serverSocket.accept();
            //3.获取输入端输入流
            inputStream = socket.getInputStream();
            //4.建立本地的存储文件
            fileOutputStream = new FileOutputStream(new File("12.png"));
            //5.获取字节过程
            byte[] buffer = new byte[1024];
            int len;
            while((len = inputStream.read(buffer)) != -1){
                fileOutputStream.write(buffer,0,len);
            }
            //5.5 服务器端给与客户端反馈
            outputStream = socket.getOutputStream();
            outputStream.write("服务器给客户端的反馈".getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //6.关闭流
            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();
                }
            }
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

2.UDP

udp实现发送端发送数据，接收端控制台显示接受数据

package top.oneluckyguy.socket;

import org.junit.Test;

import javax.swing.plaf.basic.BasicButtonUI;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.Socket;

/**
 * @author Liu Qingfeng
 * @create 2020-12-21----14:06
 * UDP协议的网络编程
 */
public class UDPTest1 {
    //发送端
    @Test
    public void sender(){
        DatagramSocket datagramSocket = null;
        try {
            datagramSocket = new DatagramSocket();
            byte[] data = "UDP 发送".getBytes();
            InetAddress inetAddress = InetAddress.getLocalHost();
            DatagramPacket datagramPacket = new DatagramPacket(data,0,data.length,inetAddress,8787);
            datagramSocket.send(datagramPacket);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (datagramSocket != null){
                datagramSocket.close();
            }
        }

    }
    //接收端
    @Test
    public void receiver(){
        DatagramSocket datagramSocket = null;
        try {
            datagramSocket = new DatagramSocket(8787);
            byte[] bytes = new byte[100];
            DatagramPacket datagramPacket = new DatagramPacket(bytes,0,bytes.length);
            datagramSocket.receive(datagramPacket);
            System.out.println(new String (datagramPacket.getData(),0,datagramPacket.getLength()));
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (datagramSocket != null){
                datagramSocket.close();
            }
        }

    }
}

3.URL网络编程

一些方法：

package top.oneluckyguy.socket;

import java.net.MalformedURLException;
import java.net.URL;

/**
 * URL网络编程
 * 1.URL:统一资源定位符，对应着互联网的某一资源地址
 * 2.格式：
 *  http://localhost:8080/examples/beauty.jpg?username=Tom
 *  协议   主机名    端口号  资源地址           参数列表
 *
 */
public class URLTest {

    public static void main(String[] args) {

        try {

            URL url = new URL("http://localhost:8080/examples/beauty.jpg?username=Tom");

//            public String getProtocol(  )     获取该URL的协议名
            System.out.println(url.getProtocol());
//            public String getHost(  )           获取该URL的主机名
            System.out.println(url.getHost());
//            public String getPort(  )            获取该URL的端口号
            System.out.println(url.getPort());
//            public String getPath(  )           获取该URL的文件路径
            System.out.println(url.getPath());
//            public String getFile(  )             获取该URL的文件名
            System.out.println(url.getFile());
//            public String getQuery(   )        获取该URL的查询名
            System.out.println(url.getQuery());




        } catch (MalformedURLException e) {
            e.printStackTrace();
        }

    }


}

实现url下载资源，要启动tomcat

package top.oneluckyguy.socket;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;


public class URLTest1 {

    public static void main(String[] args) {

        HttpURLConnection urlConnection = null;
        InputStream is = null;
        FileOutputStream fos = null;
        try {
            URL url = new URL("http://localhost:8080/examples/beauty.jpg");

            urlConnection = (HttpURLConnection) url.openConnection();

            urlConnection.connect();

            is = urlConnection.getInputStream();
            fos = new FileOutputStream("day10\\beauty3.jpg");

            byte[] buffer = new byte[1024];
            int len;
            while((len = is.read(buffer)) != -1){
                fos.write(buffer,0,len);
            }

            System.out.println("下载完成");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //关闭资源
            if(is != null){
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(fos != null){
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(urlConnection != null){
                urlConnection.disconnect();
            }
        }

    }
}