[网络协议]网络编程。

package com.www.java1;

import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * 一、网络编程中有两个主要的问题：
 * ?如何准确地定位网络上一台或多台主机；定位主机上的特定的应用
 * ?找到主机后如何可靠高效地进行数据传输
 *
 * 二、网络编程中的两个要素
 * 1.对应问题一，IP和端口号
 * 2.对应问题二，网络通信协议：TCP/IP参考模型（应用层、传输层、网络层、物理+数据链路层）
 *
 * 三、通信要素一：IP和端口号
 * 1.IP：唯一的标识Internet上的计算机（通信实体）
 * 2.在Java中使用InetAdress类代表IP
 * 3.IP分类：IPv4和IPv6；万维网和局域网
 * 4.域名：www.baidu.com等
 * 5.本地回路地址：127.0.0.1 对应着：localhost
 * 6.如何实例化InetAddress，两个方法：getByname(String host)，getlocalHost()
 * 7.端口号：标识正在计算机上运行的进程（程序）
 *   不同的进程有不同的端口号
 *   被规定为一个 16 位的整数 0~65535。
 * 8.端口号与IP地址的组合得出一个网络套接字：Socket。
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class InetAdressTest {
    public static void main(String[] args) {
        try {
            InetAddress name = InetAddress.getByName("192.168.10.14");
            System.out.println(name);
            InetAddress name1 = InetAddress.getByName("www.baidu.com");
            System.out.println(name1);
            InetAddress localHost = InetAddress.getLocalHost();
            System.out.println(localHost);


            System.out.println(name1.getHostName());//获取域名
            System.out.println(name.getHostAddress());//获取IP地址


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

package com.www.java1;

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;

/**
 * 实现TCP的网络编程
 *例子：客户端发送数据给服务端，服务端显示数据在控制台上
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class TCPTest1 {

    //客户端
    @Test
    public void client(){
        Socket socket = null;
        OutputStream outputStream = null;
        try {
            //1.创建Socket对象，获取ip和端口
            InetAddress host = InetAddress.getByName("127.0.0.1");
            socket = new Socket(host, 8899);
            //2.获取输出流，用于输出数据
            outputStream = socket.getOutputStream();
            //3.写出数据
            outputStream.write("你好，我是客户端".getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //4.资源关闭
            try {
                if(socket != null)
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(socket != null)
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    //服务端
    @Test
    public void server(){
        ServerSocket serverSocket = null;
        Socket accept = null;
        InputStream inputStream = null;
        ByteArrayOutputStream bao = null;
        try {
            //1.创建ServerSocket，指明自己的端口
            serverSocket = new ServerSocket(8899);
            //2.调用accept()，接收客户端的socket
            accept = serverSocket.accept();
            //3.获取输入流
            inputStream = accept.getInputStream();
            //可能有乱码
//        byte[] bytes = new byte[1024];
//        int len;
//        while((len = inputStream.read(bytes))!= -1){
//            String s = new String(bytes, 0, len);
//            System.out.print(s);
//        }
            bao = new ByteArrayOutputStream();
            byte[] bytes = new byte[5];
            int len;
            while((len = inputStream.read(bytes))!= -1){
                bao.write(bytes,0, len);
            }
            System.out.println(bao.toString());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if(bao != null)
                bao.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(inputStream != null)
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(accept != null)
                accept.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(serverSocket != null)
                serverSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

package com.www.java1;

import org.junit.Test;

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

/**
 * 例子：客户端发送文件给服务端，服务端将文件保存在本地。
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class TCPTest2 {

    @Test
    public void client(){
        FileInputStream filestream = null;
        Socket socket = null;
        OutputStream outputStream = null;
        try {
            //1.原有文件读入内存
            File file = new File("hihello.txt");
            filestream = new FileInputStream(file);
            //2.IP和端口
            InetAddress host = InetAddress.getByName("127.0.0.1");
            socket = new Socket(host, 8898);
            //3.输出流
            outputStream = socket.getOutputStream();

            byte[] bytes = new byte[12];
            int len;
            //4.向服务器写出数据
            while((len = filestream.read(bytes))!= -1){
                outputStream.write(bytes,0,len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭
            try {
                if(outputStream != null)
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(socket != null)
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(filestream != null)
                filestream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    @Test
    public void server(){
        FileOutputStream fileOutputStream = null;
        ServerSocket serverSocket = null;
        Socket accept = null;
        InputStream inputStream = null;
        try {
            //1.目标文件写出流
            fileOutputStream = new FileOutputStream(new File("lalala.txt"));
            //2.设置端口和接收
            serverSocket = new ServerSocket(8898);
            accept = serverSocket.accept();
            //3.获取输入流
            inputStream = accept.getInputStream();
            //4.读入并写出
            byte[] bytes = new byte[5];
            int len;
            while((len = inputStream.read(bytes)) != -1){
                fileOutputStream.write(bytes, 0, len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭流
            try {
                if(inputStream != null)
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(accept != null)
                accept.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(serverSocket != null)
                serverSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(fileOutputStream != null)
                fileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

package com.www.java1;

import org.junit.Test;

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

/**
 * 例子：从客户端发送文件给服务端，服务端保存到本地。并返回“发送成功”给
 * 客户端。并关闭相应的连接。
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class TCPTest3 {
    @Test
    public void client(){
        FileInputStream filestream = null;
        Socket socket = null;
        OutputStream outputStream = null;
        ServerSocket serverSocket = null;
        ByteArrayOutputStream bao = null;
        try {
            //1.原有文件读入内存
            File file = new File("hihelloha.txt");
            filestream = new FileInputStream(file);
            //2.IP和端口
            InetAddress host = InetAddress.getByName("127.0.0.1");
            socket = new Socket(host, 8898);
            //3.输出流
            outputStream = socket.getOutputStream();

            byte[] bytes = new byte[12];
            int len;
            //4.向服务器写出数据
            while((len = filestream.read(bytes))!= -1){
                outputStream.write(bytes,0,len);
            }
            socket.shutdownOutput();
            //5.创建端口，接收信息

            InputStream inputStream = socket.getInputStream();
            bao = new ByteArrayOutputStream();
            byte[] bytes1 = new byte[5];
            int len1;
            while((len1 = inputStream.read(bytes1))!= -1){
                bao.write(bytes1,0, len1);
            }
            System.out.println(bao.toString());

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭
            try {if(bao != null)
                bao.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(outputStream != null) {
                    outputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(socket != null) {
                    socket.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(filestream != null) {
                    filestream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    @Test
    public void server(){
        FileOutputStream fileOutputStream = null;
        ServerSocket serverSocket = null;
        Socket accept = null;
        InputStream inputStream = null;
        OutputStream outputStream = null;
        try {
            //1.目标文件写出流
            fileOutputStream = new FileOutputStream(new File("lalalala.txt"));
            //2.设置端口和接收
            serverSocket = new ServerSocket(8898);
            accept = serverSocket.accept();
            //3.获取输入流
            inputStream = accept.getInputStream();
            //4.读入并写出
            byte[] bytes = new byte[5];
            int len;
            while((len = inputStream.read(bytes)) != -1){
                fileOutputStream.write(bytes, 0, len);
            }
            //5.发送接收成功
            outputStream = accept.getOutputStream();
            outputStream.write("接收成功".getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.关闭流
            try {
                if(outputStream != null)
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(inputStream != null)
                    inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(accept != null)
                    accept.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(serverSocket != null)
                    serverSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(fileOutputStream != null)
                    fileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}

package com.www.java1;

import org.junit.Test;

import javax.xml.crypto.Data;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

/**
 * UDP协议的网络编程
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class UDPTest {
    //未抛异常
    @Test
    public void send(){
        DatagramSocket socket = new DatagramSocket();

        String str = "你瞅啥？瞅你咋地！";
        byte[] data = str.getBytes();
        InetAddress localHost = InetAddress.getLocalHost();
        DatagramPacket packet = new DatagramPacket(data,0,data.length,localHost,9090);

        socket.send(packet);

        socket.close();

    }

    @Test
    public void recevie(){
        DatagramSocket socket = new DatagramSocket(9090);

        byte[] data = new byte[100];
        DatagramPacket packet = new DatagramPacket(data,0,data.length);//数据放在data中
        socket.receive(packet);//接收放在packet

        System.out.println(new String(packet.getData(),0,packet.getLength()));

        socket.close();
    }
}

package com.www.java1;

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

/**
 * URL网络编程
 * 1.URL：统一资源定位符，对应着Internet上的某一资源地址
 * 2.格式：
 *      <传输协议>://<主机名>:<端口号>/<文件名>#片段名?参数列表
 *  例如:
 *      http://192.168.1.100:8080/helloworld/index.jsp#a?username=shkstart&password=123
 * @author www
 * @creat 2022-{MONTH}-{DAY}
 */
public class URLTest {
    public static void main(String[] args) {
        HttpURLConnection urlConnection = null;
        InputStream inputStream = null;
        FileOutputStream fileOutputStream = null;
        try {
            //建立连接(运行后图片没有加载出来？)
            URL url = new URL("https://cn.bing.com/images/search?view=detailV2&ccid=AOdA8t0u&id=CA9B72EB873CA982050100C2E3D5E01C9BF4CFC6&thid=OIP.AOdA8t0ufnqy7JtKMYvMDQHaNK&mediaurl=https%3a%2f%2fuploadfile.bizhizu.cn%2fup%2fc7%2fcb%2f02%2fc7cb02e48dfecc2c1ce20baadc32af50.jpg&exph=1820&expw=1024&q=%e5%88%98%e4%ba%a6%e8%8f%b2&simid=608054175508419144&FORM=IRPRST&ck=DEE0576FC7DDC44BA2AEC6E8C29728A0&selectedIndex=0&ajaxhist=0&ajaxserp=0");
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.connect();
            //输入流
            inputStream = urlConnection.getInputStream();
            //输出文件
            fileOutputStream = new FileOutputStream("Day10\\刘亦菲.jpeg");

            byte[] bytes = new byte[1024];
            int len;
            while((len = inputStream.read(bytes)) != -1){
                fileOutputStream.write(bytes, 0, len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if(fileOutputStream != null)
                fileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if(inputStream != null)
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            urlConnection.disconnect();
        }


    }
}