Java如何实现URL带请求参数(get/post)及得到get和post请求url和参数列表的方法

public static String sendGet(String url,String param) { String result = ""; try{ String urlName = url + "?"+param;// URL U = new URL(urlName); URLConnection connection = U.openConnection(); connection.connect(); BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream())); String line; while ((line = in.readLine())!= null) { result += line; } in.close();  }catch(Exception e){ System.out.println("Helloword！！"+e); } return result; } public static String sendPost(String url,String param) { String result=""; try{ URL httpurl = new URL(url); HttpURLConnection httpConn = (HttpURLConnection)httpurl.openConnection();   httpConn.setDoOutput(true); httpConn.setDoInput(true); PrintWriter out = new PrintWriter(httpConn.getOutputStream()); out.print(param); out.flush(); out.close(); BufferedReader in = new BufferedReader(new InputStreamReader(httpConn.getInputStream())); String line; while ((line = in.readLine())!= null) { result += line;  } in.close(); }catch(Exception e){ System.out.println("Helloword！"+e); } return result; }

package com.zuidaima       import java.io.IOException; import java.io.PrintWriter; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class GetParams extends HttpServlet {  private static final long serialVersionUID = 1L;  public GetParams() {   super();  }  protected void doGet(HttpServletRequest request,    HttpServletResponse response) throws ServletException, IOException {   PrintWriter writer = response.getWriter();   writer.println("GET " + request.getRequestURL() + " "     + request.getQueryString());   Map<String, String[]> params = request.getParameterMap();   String queryString = "";   for (String key : params.keySet()) {    String[] values = params.get(key);    for (int i = 0; i < values.length; i++) {     String value = values[i];     queryString += key + "=" + value + "&";    }   }   // 去掉最后一个空格   queryString = queryString.substring(0, queryString.length() - 1);   writer.println("GET " + request.getRequestURL() + " " + queryString);  }  protected void doPost(HttpServletRequest request,    HttpServletResponse response) throws ServletException, IOException {   PrintWriter writer = response.getWriter();   Map<String, String[]> params = request.getParameterMap();   String queryString = "";   for (String key : params.keySet()) {    String[] values = params.get(key);    for (int i = 0; i < values.length; i++) {     String value = values[i];     queryString += key + "=" + value + "&";    }   }   // 去掉最后一个空格   queryString = queryString.substring(0, queryString.length() - 1);   writer.println("POST " + request.getRequestURL() + " " + queryString);  } }