JavaWEB project custom filter

Character encoding filter

package com.soft.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;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebFilter("/EncodeFilter")
public class EncodeFilter implements Filter {

	private String encoding;

	public EncodeFilter() {

	}

	public void init(FilterConfig fConfig) throws ServletException {

		encoding = fConfig.getInitParameter("encode");
	}

	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
			throws IOException, ServletException {
		
			HttpServletRequest req = (HttpServletRequest)request;
			HttpServletResponse res = (HttpServletResponse)response;
			
			req.setCharacterEncoding(encoding);
			res.setCharacterEncoding(encoding);
			System.out.println("过滤器加载");
		chain.doFilter(req, res);

	}

	// 实现销毁方法
	public void destroy() {
		
		
	}

}

Login filter

package com.soft.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;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebFilter("/LoginFilter")
public class LoginFilter implements Filter {

    public LoginFilter() {
    }

	public void destroy() {
		
	}
	
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
		

		HttpServletRequest req = (HttpServletRequest)request;
		HttpServletResponse res = (HttpServletResponse)response;
		
		String name = (String)req.getSession().getAttribute("username");
		
		System.out.println("未登录过滤");
		
		if(name==null) {
			res.sendRedirect("index.jsp");
		}else {
			
			chain.doFilter(request, response);
		}
	
		
		
		
		
		
	}

	public void init(FilterConfig fConfig) throws ServletException {
		
	}
	

}

 

 

 

 

web.xml reference

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
  <display-name>EShop</display-name>
  <welcome-file-list>
    <welcome-file>jsp/front/index.jsp</welcome-file>
  </welcome-file-list>
  <filter>
    <filter-name>EncodeFilter</filter-name>
    <filter-class>com.soft.filter.EncodeFilter</filter-class>
    <init-param>
      <param-name>encode</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>EncodeFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <filter>
    <filter-name>LoginFilter</filter-name>
    <filter-class>com.soft.filter.LoginFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>LoginFilter</filter-name>
    <url-pattern>/jsp/front/frontmanager.jsp</url-pattern>
  </filter-mapping>
</web-app>