Java HTTP通信--Get与POST请求

一、JDK自带的http通信机制--java.net.URL

package com.wjy;

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;
import java.net.URLConnection;

public class TestURL {

    public static void main(String[] args) {
        new GetRun().start();//get请求
        new PostRun().start();//post请求
    }

}

class GetRun extends Thread{
    public void run() {
        try {
            //doctype=xml/json/jsonp
            URL url = new URL("http://fanyi.youdao.com/openapi.do?keyfrom=wjy-test&key=36384249&type=data&doctype=jsonp&callback=show&version=1.1&q=hello");
            URLConnection connection = url.openConnection();
            InputStream in = connection.getInputStream();
            InputStreamReader isr = new InputStreamReader(in,"utf-8");
            BufferedReader br = new BufferedReader(isr);
            String line;
            StringBuilder sb = new StringBuilder();
            while((line = br.readLine()) != null)
            {
                sb.append(line);
            }
            br.close();
            isr.close();
            in.close();
            System.out.println(sb.toString());
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}


class PostRun 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");//添加请求属性
            connection.setDoInput(true);//允许输入
            connection.setDoOutput(true);//允许输出
            connection.setRequestMethod("POST");//POST请求 要在获取输入输出流之前设置  否则报错
            //输出
            OutputStream os = connection.getOutputStream();
            OutputStreamWriter osw = new OutputStreamWriter(os);
            BufferedWriter bw = new BufferedWriter(osw);
            bw.write("keyfrom=wjy-test&key=36384249&type=data&doctype=xml&version=1.1&q=welcome");
            bw.flush();
            
            //输入
            InputStream in = connection.getInputStream();
            InputStreamReader isr = new InputStreamReader(in,"UTF-8");
            BufferedReader br = new BufferedReader(isr);
            
            String line;
            StringBuilder sb = new StringBuilder();
            while((line = br.readLine()) != null)
            {
                sb.append(line);
            }
            bw.close();
            osw.close();
            os.close();
            br.close();
            isr.close();
            in.close();
            
            System.out.println(sb.toString());
            
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        
    }
    
}

 

二、apache中HttpComponents项目HttpClient工具

package com.wjy;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

public class TestHttpclient {

    /**
     * 从apache官网下载HttpComponents项目jar包
     */
    public static void main(String[] args) {
        //new Get().start();
        new Post().start();
    }

}


class Get extends Thread{
    HttpClient client = HttpClients.createDefault();
    
    @Override
    public void run() {
        HttpGet get = new HttpGet("http://www.baidu.com");
        try {
            HttpResponse response = client.execute(get);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println(result);
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        
    }
}


class Post extends Thread{
HttpClient client = HttpClients.createDefault();
    
    @Override
    public void run() {
        HttpPost post = new HttpPost("http://fanyi.youdao.com/openapi.do");
        try {
            List<BasicNameValuePair> parameters = new ArrayList<BasicNameValuePair>();
            parameters.add(new BasicNameValuePair("keyfrom", "wjy-test"));
            parameters.add(new BasicNameValuePair("key", "36384249"));
            parameters.add(new BasicNameValuePair("type", "data"));
            parameters.add(new BasicNameValuePair("doctype", "xml"));
            parameters.add(new BasicNameValuePair("version", "1.1"));
            parameters.add(new BasicNameValuePair("q", "welcome"));
            post.setEntity(new UrlEncodedFormEntity(parameters));
            HttpResponse response = client.execute(post);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println(result);
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        
    }
}

 

来源：https://www.cnblogs.com/cac2020/p/6675794.html