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);      }      }