//创建ErrorFilter
package com.filter;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
public class ErrorFilter implements Filter {
@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
throws IOException, ServletException {
arg2.doFilter(arg0, arg1);
}
@Override
public void init(FilterConfig arg0) throws ServletException {
}
}
//页面index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<h1>这是一个JSP</h1>
</body>
</html>
//页面error.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<%
response.setStatus(200);//想在eclipse自带的浏览器看到错误就加上这句
%>
<body>
<h1>抱歉,您输入的路径有误!</h1>
</body>
</html>
//写web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>JavaWeb_001_fistFilter</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<filter>
<filter-name>ErrorFilter</filter-name>
<filter-class>com.filter.ErrorFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>ErrorFilter</filter-name>
<url-pattern>/index.jsp</url-pattern>
<dispatcher>ERROR</dispatcher> //记得加上这个,不然是默认的
</filter-mapping>
<error-page>
<error-code>404</error-code>
<location>/error.jsp</location>
</error-page>
</web-app><url-pattern>/index.jsp</url-pattern>
这个写错了你这个变成了当请求index.jsp的时候才会调用errorfilter
应该是
<url-pattern>/error.jsp</url-pattern>
这样就是正确的了