java跨服務器請求url獲得數據

在項目中，有時需要通過請求遠程服務器上的url獲取數據(前提是程序所在服務器可以和url服務器ping成功),

用java在后台發送請求時，用到了java.net.URL, java.net.URLConnection,

以下是分別用post和get方式請求url的簡單工具類實現:

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;
import java.util.Map;

public class CallWebPage {
    /**
     * 用get方式連接url
     * @param urlString url路徑
     * @param pdata    url參數
     * @return 從url獲得的數據
     */
    public static String CallWebPageGet(String urlString,String pdata) {
        String result="";
        PrintWriter out = null;  
        BufferedReader in = null; 
        URL url=null;
        try {
            url = new URL(urlString+"?"+pdata);//用url路徑以及所用參數創建URL實例類
            URLConnection connect = url.openConnection();//創建連接
            connect.setRequestProperty("content-type","application/x-www-form-urlencoded;charset=utf-8");//設置請求header的屬性--請求內容類型
            connect.setRequestProperty("method","GET");//設置請求header的屬性值--請求方式
            // 建立實際的連接  
            connect.connect();  //建立與url所在服務器的連接
            // 獲取所有響應頭字段  
            Map<String, List<String>> map = connect.getHeaderFields();  
            // 遍歷所有的響應頭字段  
            for (String key : map.keySet()) {  
                System.out.println(key + "--->" + map.get(key));  
            }  
            // 定義BufferedReader輸入流來讀取URL的響應  
            in = new BufferedReader(new InputStreamReader(connect.getInputStream()));  
            String line="";  
            while ((line = in.readLine()) != null) {  
                result +=  line;  
            }  
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        return result;
    }
    /**
     * 用gpost方式連接url
     * @param urlString url路徑
     * @param pdata    url參數
     * @return 從url獲得的數據
     */
    public static String CallWebPagePost(String urlString,String pdata) {
        String result="";
        PrintWriter out = null;  
        BufferedReader in = null; 
        URL url=null;
        try {
            url = new URL(urlString);
            URLConnection connect = url.openConnection();
            connect.setRequestProperty("content-type","application/x-www-form-urlencoded;charset=utf-8");
            connect.setRequestProperty("method","POST");
            byte[] bytes= pdata.getBytes("utf-8") ;
            connect.setDoOutput(true);  
            connect.setDoInput(true);  
            
            out = new PrintWriter(connect.getOutputStream());  
            // 發送請求參數  
            out.print(pdata);
            out.flush();  
            // 定義BufferedReader輸入流來讀取URL的響應  
            in = new BufferedReader(new InputStreamReader(connect.getInputStream()));  
            String line;  
            while ((line = in.readLine()) != null) {  
                result +=  line;  
            }      
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        return result;
    }
}