package com.sxt.in; import java.io.IOException; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; /**
* Service方法和doget 和 dopost方法的区别：
* doget：
* 处理get请求方式
* dopost：
* 处理post请求方式
*
* Service：
* 优先处理，
*
* 注意：
* 如果在覆写的service方法中调用了父类的service方法（super.service(arg0, arg1);
* 则在service方法处理完成时会在次根据请求方式调用doget和dopost方法
* 一般我们不在覆写service中调用父类的方法，避免出现405错误。
* Servlet的常见错误
* 404错误：资源未找到
* 原因一：在请求地址中的servlet别名书写错误
* 原因二：虚拟项目名称书写错误
* 500错误： 内部服务器错误
* 错误一 <servlet-class>com.sxt.in.ServletMthod</servlet-class>
* 解决
* 在web.xml中校检servlet类的全限路径是否拼写 错误.
* 错误二
* 因为service方法体中的代码执行错误
*
* 解决：根据错误提示对代码进行更改
* 405错误：请求方式不支持
* 原因：
* 请求方式和service中的方法不匹配所造成的的
* 解决：
* 尽量使用service方法处理请求，并且在service方法中不要调用父类的service方法
* @author Administrator
* Ctrl+F 查找别名
*/
public class ServletMethod extends HttpServlet {
// @Override
// protected void service(HttpServletRequest req, HttpServletResponse resp)
// throws ServletException, IOException {
// System.out.println("我是service");
//
// }
@Override
protected void service(HttpServletRequest arg0, HttpServletResponse arg1)
throws ServletException, IOException {
// TODO Auto-generated method stub
super.service(arg0, arg1);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
System.out.println("我说dogetservice");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
System.out.println("我是dopost方法");
} }
ServeletMethod.java以上
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>"> <title>My JSP 'MethodJsp.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
--> </head> <body> <form action="method" method="get">
用户名:<input type="text" name="uname" value=""><br />
密码:<input type="password" name="pwd" value=""><br />
<input type="submit" value="登录"> </form>
</body>
</html>
jsp
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>servletlife</servlet-name>
<servlet-class>com.sxt.in.servletlife</servlet-class>
<load-on-startup>1</load-on-startup><!-- 加载服务器启动流 其中的数字1表示项目的加载顺序-->
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>ServletMethod</servlet-name>
<servlet-class>com.sxt.in.ServletMethod</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>servletlife</servlet-name>
<url-pattern>/life</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ServletMethod</servlet-name>
<url-pattern>/method</url-pattern>
</servlet-mapping> </web-app>
xml代码