Java調用Rest請求

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 {
	/**
	 * 實現對REST服務的請求
	 * @param urlStr
	 * @param urlParam
	 * @return
	 * @throws java.io.IOException
	 */
	public static String httpGet(String urlStr, List<String> urlParam) throws IOException{
		if (!urlParam.isEmpty()) {
			urlStr += "?";
			// 定義一個迭代器，並將MAP值的集合賦值
			for (String string : urlParam) {
				urlStr += string + "&";
			}
			urlStr = urlStr.substring(0, urlStr.length() - 1);
		}
		// 實例一個URL資源
		URL url = new URL(urlStr);
	    //實例一個HTTP CONNECT
	    HttpURLConnection connet = (HttpURLConnection) url.openConnection();
	    connet.setRequestMethod("GET");
	    connet.setRequestProperty("Charset", "UTF-8");
	    connet.setRequestProperty("Content-Type", "application/json");
	    connet.setConnectTimeout(15000);// 連接超時 單位毫秒
	    connet.setReadTimeout(15000);// 讀取超時 單位毫秒 
	    if(connet.getResponseCode() != 200){
	        System.out.println("請求異常" + urlStr);
	        return "";
	    }
	    //將返回的值存入到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();
	}
}