基于HttpURLConnection的接口调用，支持GET&POST

单位要做一个多级部署平台，大概意思就是一级系统可以监控下属地域的数据也可管理本地的数据。之前做短信猫用过httpClient请求，与此大同小异。封装了一个两种请求方式的工具类。

package com.subordinate.util;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

/**
 * 接口调用工具类
 *     目前支持 GET POST请求两种方式
 *
 * @author Together
 *
 *@date 2018年4月17日
 */
public class HttpURLConnectionUtil {

    /**
     * get请求
     *
     * @param url
     * @param param
     * @return
     */
    public static String get(String url,Map<String, Object> param) {
        StringBuilder builder=new StringBuilder();
        try {
            StringBuilder params=new StringBuilder();
            for(Entry<String, Object> entry:param.entrySet()){
                params.append(entry.getKey());
                params.append("=");
                params.append(entry.getValue().toString());
                params.append("&");
            }
            if(params.length()>){
                params.deleteCharAt(params.lastIndexOf("&"));
            }
            URL restServiceURL = new URL(url+(params.length()> ? "?"+params.toString() : ""));
            HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL.openConnection();
            httpConnection.setRequestMethod("GET");
            httpConnection.setRequestProperty("Accept", "application/json");
            if (httpConnection.getResponseCode() != ) {
                throw new RuntimeException("HTTP GET Request Failed with Error code : "
                              + httpConnection.getResponseCode());
         }
            InputStream inStrm = httpConnection.getInputStream();
            byte []b=new byte[];
            int length=-;
            while((length=inStrm.read(b))!=-){
                builder.append(new String(b,,length));
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return builder.toString();
    }
    /**
     * post    请求
     *
     * @param url
     * @param param
     * @return
     */
    public static String post(String url,Map<String, Object> param) {
        StringBuilder builder=new StringBuilder();
        try {
            StringBuilder params=new StringBuilder();
            for(Entry<String, Object> entry:param.entrySet()){
                params.append(entry.getKey());
                params.append("=");
                params.append(entry.getValue().toString());
                params.append("&");
            }
            if(params.length()>){
                params.deleteCharAt(params.lastIndexOf("&"));
            }
            URL restServiceURL = new URL(url+(params.length()> ? "?"+params.toString() : ""));
            HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL.openConnection();
            httpConnection.setRequestMethod("POST");
            httpConnection.setRequestProperty("Accept", "application/json");
            // 设置是否从httpUrlConnection读入，默认情况下是true;
            httpConnection.setDoInput(true);
            // Post 请求不能使用缓存
            httpConnection.setUseCaches(false);
            if (httpConnection.getResponseCode() != ) {
                throw new RuntimeException("HTTP POST Request Failed with Error code : "
                              + httpConnection.getResponseCode());
         }
            InputStream inStrm = httpConnection.getInputStream();
            byte []b=new byte[];
            int length=-;
            while((length=inStrm.read(b))!=-){
                builder.append(new String(b,,length));
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return builder.toString();
    }

    public static void main(String[] args) {
        String urlString="http://localhost:8080/vms/subordinate/testController/test";
        Map<String, Object> param=new HashMap<String, Object>();
        param.put("userId", "");
        param.put("pa", "hello");
        HttpURLConnectionUtil.get(urlString, param);
        HttpURLConnectionUtil.post(urlString, param);
    }
}