java后台调用HttpURLConnection类模拟浏览器请求(一般用于接口调用)

 项目开发中难免遇到外部接口的调用,小生今天初次接触该类,跟着API方法走了一遍,如有不对的地方,还请哆哆指正,拜谢!

 1 package com.cplatform.movie.back.test;
  2 
  3 import java.io.BufferedReader;
  4 import java.io.DataOutputStream;
  5 import java.io.InputStreamReader;
  6 import java.net.HttpURLConnection;
  7 import java.net.URL;
  8 import java.net.URLEncoder;
  9 
 10 
 11 
 12 public class HttpURLConnectionTest {
 13     public static final String GET_URL = "http://112.4.27.9/mall-back/if_user/store_list?storeId=32";
 14     public static final String POST_URL = "http://112.4.27.9/mall-back/if_user/store_list";
 15     
 16     /**
 17      * 接口调用 GET
 18      */
 19     public static void httpURLConectionGET() {
 20         try {
 21             URL url = new URL(GET_URL);    // 把字符串转换为URL请求地址
 22             HttpURLConnection connection = (HttpURLConnection) url.openConnection();// 打开连接
 23             connection.connect();// 连接会话
 24             // 获取输入流
 25             BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
 26             String line;
 27             StringBuilder sb = new StringBuilder();
 28             while ((line = br.readLine()) != null) {// 循环读取流
 29                 sb.append(line);
 30             }
 31             br.close();// 关闭流
 32             connection.disconnect();// 断开连接
 33             System.out.println(sb.toString());
 34         } catch (Exception e) {
 35             e.printStackTrace();
 36             System.out.println("失败!");
 37         }
 38     }
 39     
 40     /**
 41      * 接口调用  POST
 42      */
 43     public static void httpURLConnectionPOST () {
 44         try {
 45             URL url = new URL(POST_URL);
 46             
 47             // 将url 以 open方法返回的urlConnection  连接强转为HttpURLConnection连接  (标识一个url所引用的远程对象连接)
 48             HttpURLConnection connection = (HttpURLConnection) url.openConnection();// 此时cnnection只是为一个连接对象,待连接中
 49             
 50             // 设置连接输出流为true,默认false (post 请求是以流的方式隐式的传递参数)
 51             connection.setDoOutput(true);
 52             
 53             // 设置连接输入流为true
 54             connection.setDoInput(true);
 55             
 56             // 设置请求方式为post
 57             connection.setRequestMethod("POST");
 58             
 59             // post请求缓存设为false
 60             connection.setUseCaches(false);
 61             
 62             // 设置该HttpURLConnection实例是否自动执行重定向
 63             connection.setInstanceFollowRedirects(true);
 64             
 65             // 设置请求头里面的各个属性 (以下为设置内容的类型,设置为经过urlEncoded编码过的from参数)
 66             // application/x-javascript text/xml->xml数据 application/x-javascript->json对象 application/x-www-form-urlencoded->表单数据
 67             connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
 68             
 69             // 建立连接 (请求未开始,直到connection.getInputStream()方法调用时才发起,以上各个参数设置需在此方法之前进行)
 70             connection.connect();
 71             
 72             // 创建输入输出流,用于往连接里面输出携带的参数,(输出内容为?后面的内容)
 73             DataOutputStream dataout = new DataOutputStream(connection.getOutputStream());
 74             String parm = "storeId=" + URLEncoder.encode("32", "utf-8"); //URLEncoder.encode()方法  为字符串进行编码
 75             
 76             // 将参数输出到连接
 77             dataout.writeBytes(parm);
 78             
 79             // 输出完成后刷新并关闭流
 80             dataout.flush();
 81             dataout.close(); // 重要且易忽略步骤 (关闭流,切记!) 
 82             
 83             System.out.println(connection.getResponseCode());
 84             
 85             // 连接发起请求,处理服务器响应  (从连接获取到输入流并包装为bufferedReader)
 86             BufferedReader bf = new BufferedReader(new InputStreamReader(connection.getInputStream())); 
 87             String line;
 88             StringBuilder sb = new StringBuilder(); // 用来存储响应数据
 89             
 90             // 循环读取流,若不到结尾处
 91             while ((line = bf.readLine()) != null) {
 92                 sb.append(bf.readLine());
 93             }
 94             bf.close();    // 重要且易忽略步骤 (关闭流,切记!) 
 95             connection.disconnect(); // 销毁连接
 96             System.out.println(sb.toString());
 97     
 98         } catch (Exception e) {
 99             e.printStackTrace();
100         }
101     }
102     
103     
104     public static void main(String[] args) {
105 //        httpURLConectionGET();
106         httpURLConnectionPOST();
107     }
108 }