用AjaxProxyServlet 跨域ajax请求

老庄的代码里用了DataInputStream，这个类的readLine()不被推荐使用，所以换成了 InputStreamReader
添加了代码来处理Ajax请求中的参数。
java 代码

/*
 * Created on 2007-1-16
 */
import javax.servlet.http.HttpServlet;  import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter;  import java.net.URL;  import java.util.Enumeration;  import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;  public class AjaxProxyServlet extends HttpServlet {     protected void service(HttpServletRequest req,                             HttpServletResponse resp) throws ServletException,                                                              IOException {         resp.setContentType("text/html");         PrintWriter pw = resp.getWriter();         Enumeration paramNames = req.getParameterNames();         StringBuffer bfParams = new StringBuffer();         bfParams.append(req.getParameter("url")).append("?1=1");         while(paramNames.hasMoreElements()) {             String param = (String)paramNames.nextElement();             if("url".equals(param)){continue;}             bfParams.append("&").append(param).append("=").append(req.getParameter(param));         }                  URL url = new URL(bfParams.toString());         BufferedReader bf =              new BufferedReader(new InputStreamReader(url.openStream()));         String line;         while ((line = bf.readLine()) != null) {             pw.println(line);         }         bf.close();     } }