Java调用Rest请求

package com.db;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;

public class RestUtil {
	/**
	 * 实现对REST服务的请求
	 * @param urlStr
	 * @param urlParam
	 * @return
	 * @throws java.io.IOException
	 */
	public static String httpGet(String urlStr, List<String> urlParam) throws IOException{
		if (!urlParam.isEmpty()) {
			urlStr += "?";
			// 定义一个迭代器，并将MAP值的集合赋值
			for (String string : urlParam) {
				urlStr += string + "&";
			}
			urlStr = urlStr.substring(0, urlStr.length() - 1);
		}
		// 实例一个URL资源
		URL url = new URL(urlStr);
	    //实例一个HTTP CONNECT
	    HttpURLConnection connet = (HttpURLConnection) url.openConnection();
	    connet.setRequestMethod("GET");
	    connet.setRequestProperty("Charset", "UTF-8");
	    connet.setRequestProperty("Content-Type", "application/json");
	    connet.setConnectTimeout(15000);// 连接超时 单位毫秒
	    connet.setReadTimeout(15000);// 读取超时 单位毫秒 
	    if(connet.getResponseCode() != 200){
	        System.out.println("请求异常" + urlStr);
	        return "";
	    }
	    //将返回的值存入到String中
	    BufferedReader brd = new BufferedReader(new InputStreamReader(connet.getInputStream(),"UTF-8"));
	    StringBuilder  sb  = new StringBuilder();
	    String line;
	 
	    while((line = brd.readLine()) != null){
	        sb.append(line);
	    }
	    brd.close();
	    connet.disconnect();
	    return sb.toString();
	}
}