Java使用HTTP的get方法读取网络数据、使用post方法与网络交互通信

1.Java使用HTTP的get方法读取网络数据

package peixun;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

public class TestGet {

    public static void main(String[] args) {
        new ReadByGet().start();
    }
    
    static class ReadByGet extends Thread {
        
        @Override
        public void run() {
            try {
                
                URL url = new URL("http://fanyi.youdao.com/openapi.do?keyfrom=yyxiaozhan&key=1696230822&type=data&doctype=xml&version=1.1&q=welcome");
                //使用方法打开链接,并使用connection接受返回值
                URLConnection connection = url.openConnection();
                //获取connection输入流,并用is接受返回值
                InputStream is = connection.getInputStream();
                //将字节流向字符流的转换
                InputStreamReader isr = new InputStreamReader(is);
                BufferedReader br = new BufferedReader(isr);
                
                String line;
                /**
                 * StringBuilder和StringBuffer不同的地方在于 StringBuffer是线程安全的
                 * 单线程、不需要线程安全的情况下，处于性能的考虑，优先选择StringBuilder
                 */
                StringBuilder builder = new StringBuilder();
                while ((line = br.readLine())!= null) {
                    builder.append(line);
                }
                
                br.close();
                isr.close();
                is.close();
                
                System.out.println(builder.toString());
                
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        
    }

}

2.Java使用HTTP的post方法与网络交互通信

package peixun;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class TestPost {

    public static void main(String[] args) {
        new ReadByPost().start();
    }

}

class ReadByPost extends Thread{
    
    @Override
    public void run() {
        try {
            
            URL url = new URL("http://fanyi.youdao.com/openapi.do");
            HttpURLConnection connection =  (HttpURLConnection) url.openConnection();
            connection.addRequestProperty("encoding", "UTF-8");
            //设置为true，connection就可以从网络获取数据
            connection.setDoInput(true);
            //设置为true，connection就可以向网络传送数据
            connection.setDoOutput(true);
            //把访问方式换成post方式
            /**
             * 使用方法时候要先发送数据，所以OutputStream放在InputStream前面
             */
            connection.setRequestMethod("POST");
            
            //connection建立链接之后，要获取输入流和输出流
            OutputStream os = connection.getOutputStream();
            OutputStreamWriter osw = new OutputStreamWriter(os);
            BufferedWriter bw = new BufferedWriter(osw); 
            
            bw.write("keyfrom=yyxiaozhan&key=1696230822&type=data&doctype=xml&version=1.1&q=welcome");
            bw.flush();
            
            //connection建立链接之后，要获取输入流和输出流
            InputStream  is = connection.getInputStream();
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            
            //进行读取操作
            String line;
            StringBuilder builder = new StringBuilder();
            while ((line = br.readLine())!=null) {//br.readline先赋值给line，然后判断line是否为空。
                builder.append(line);
            }
            
            bw.close();
            osw.close();
            os.close();
            br.close();
            isr.close();
            is.close();
            
            System.out.println(builder.toString());
            
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
}