转自链接：http://www.cnblogs.com/panjun-Donet/archive/2009/04/04/1429585.html
Servlet eroor：HTTP method GET is not supported by this URL
错误提示：
type: Status report
message: HTTP method GET is not supported by this URL
description: The specified HTTP method is not allowed for the requested resource (HTTP method GET is not supported by this URL).
原因：
1，继承自HttpServlet的Servlet没有重写对于请求和响应的处理方法：doGet或doPost等方法；默认调用父类的doGet或doPost等方法；
2，父类HttpServlet的doGet或doPost等方法覆盖了你重写的doGet或doPost等方法；
不管是1或2，父类HttpServlet的doGet或doPost等方法的默认实现是返回状态代码为405的HTTP错误表示对于指定资源的请求方法不被允许。
解决方法：
1，子类重写doGet或doPost等方法；
2，在你扩展的Servlert中重写doGet或doPost等方法来处理请求和响应时 不要调用父类HttpServlet的doGet或doPost等方法，即去掉super.doGet(request, response)和super.doPost(request, response);
web.config的配置
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(自己代码，红色标注错误)
package servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//继承与HttpServlet
public class HelloServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// TODO Auto-generated method stub
//super.doGet(request, response);
System.out.println("处理Get请求。。。。");
response.setContentType("text/html;charset=utf-8");
PrintWriter out=response.getWriter();
out.println("HELLO SERVLET!");
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// TODO Auto-generated method stub
//super.doPost(request, response);
}
}