java实现向服务端发送GET和POST请求详解编程语言

  
package com.hongyuan.test; 
   
import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.io.PrintWriter; 
import java.net.HttpURLConnection; 
import java.net.URL; 
   
public class HttpClient { 
    //发送一个GET请求 
    public static String get(String path) throws Exception{ 
        HttpURLConnection httpConn=null; 
        BufferedReader in=null; 
        try { 
            URL url=new URL(path); 
            httpConn=(HttpURLConnection)url.openConnection(); 
               
            //读取响应 
            if(httpConn.getResponseCode()==HttpURLConnection.HTTP_OK){ 
                StringBuffer content=new StringBuffer(); 
                String tempStr=""; 
                in=new BufferedReader(new InputStreamReader(httpConn.getInputStream())); 
                while((tempStr=in.readLine())!=null){ 
                    content.append(tempStr); 
                } 
                return content.toString(); 
            }else{ 
                throw new Exception("请求出现了问题!"); 
            } 
        } catch (IOException e) { 
            e.printStackTrace(); 
        }finally{ 
            in.close(); 
            httpConn.disconnect(); 
        } 
        return null; 
    } 
    //发送一个GET请求,参数形式key1=value1&key2=value2... 
    public static String post(String path,String params) throws Exception{ 
        HttpURLConnection httpConn=null; 
        BufferedReader in=null; 
        PrintWriter out=null; 
        try { 
            URL url=new URL(path); 
            httpConn=(HttpURLConnection)url.openConnection(); 
            httpConn.setRequestMethod("POST"); 
            httpConn.setDoInput(true); 
            httpConn.setDoOutput(true); 
               
            //发送post请求参数 
            out=new PrintWriter(httpConn.getOutputStream()); 
            out.println(params); 
            out.flush(); 
               
            //读取响应 
            if(httpConn.getResponseCode()==HttpURLConnection.HTTP_OK){ 
                StringBuffer content=new StringBuffer(); 
                String tempStr=""; 
                in=new BufferedReader(new InputStreamReader(httpConn.getInputStream())); 
                while((tempStr=in.readLine())!=null){ 
                    content.append(tempStr); 
                } 
                return content.toString(); 
            }else{ 
                throw new Exception("请求出现了问题!"); 
            } 
        } catch (IOException e) { 
            e.printStackTrace(); 
        }finally{ 
            in.close(); 
            out.close(); 
            httpConn.disconnect(); 
        } 
        return null; 
    } 
       
    public static void main(String[] args) throws Exception { 
        //String resMessage=HttpClient.get("http://localhost:3000/hello?hello=hello get"); 
        String resMessage=HttpClient.post("http://localhost:3000/hello", "hello=hello post"); 
        System.out.println(resMessage); 
    } 
   
}