Filter_编码过滤，登录过滤，权限过滤

青旅半醒 2023-06-29 10:53 2阅读 0赞

## web.xml ##

<?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" id="WebApp_ID" version="3.1">
      <display-name>scm</display-name>
      <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.htm</welcome-file>
        <welcome-file>index.jsp</welcome-file>
        <welcome-file>default.html</welcome-file>
        <welcome-file>default.htm</welcome-file>
        <welcome-file>default.jsp</welcome-file>
      </welcome-file-list>
      
      <filter>
      	<filter-name>encode</filter-name>
      	<filter-class>com.scm.filter.EncodeFilter</filter-class>
      	
      	<init-param>
      		<param-name>encoding</param-name>
      		<param-value>utf-8</param-value>
      	</init-param>
      </filter>
      
      <filter>
      	<filter-name>login</filter-name>
      	<filter-class>com.scm.filter.LoginFilter</filter-class>
      </filter>
      
      <filter>
      	<filter-name>auth</filter-name>
      	<filter-class>com.scm.filter.AuthFilter</filter-class>
      </filter>
      
      
      <filter-mapping>
      	<filter-name>encode</filter-name>
      	<url-pattern>/*</url-pattern>
      </filter-mapping>
      
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/system/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/purchase/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/warehouse/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/finance/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/sale/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>login</filter-name>
      	<url-pattern>/system/*</url-pattern>
      </filter-mapping>
      
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/system/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/purchase/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/warehouse/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/finance/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/sale/*</url-pattern>
      </filter-mapping>
      <filter-mapping>
      	<filter-name>auth</filter-name>
      	<url-pattern>/system/*</url-pattern>
      </filter-mapping>
    </web-app>

## EncodeFilter ##

package com.scm.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;
    
    /**
     * Servlet Filter implementation class EncodeFilter
     */
    @WebFilter("/EncodeFilter")
    public class EncodeFilter implements Filter {
        
    	String encode;
        /**
         * Default constructor. 
         */
        public EncodeFilter() {
        
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see Filter#destroy()
    	 */
    	public void destroy() {
        
    		// TODO Auto-generated method stub
    	}
    
    	/**
    	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
    	 */
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        
    		request.setCharacterEncoding(encode);
    		response.setCharacterEncoding(encode);
    		
    		chain.doFilter(request, response);
    	}
    
    	/**
    	 * @see Filter#init(FilterConfig)
    	 */
    	public void init(FilterConfig fConfig) throws ServletException {
        
    		Filter.super.init(fConfig);
    		encode=fConfig.getInitParameter("encoding");
    	}
    
    }

## LoginFilter ##

package com.scm.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;
    
    /**
     * Servlet Filter implementation class LoginFilter
     */
    @WebFilter("/LoginFilter")
    public class LoginFilter implements Filter {
        
    
        /**
         * Default constructor. 
         */
        public LoginFilter() {
        
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see Filter#destroy()
    	 */
    	public void destroy() {
        
    		// TODO Auto-generated method stub
    	}
    
    	/**
    	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
    	 */
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        
    		HttpServletRequest req=(HttpServletRequest)request;
    		
    		Object obj = req.getSession().getAttribute("user");
    		if(obj==null) {
        //未登录
    			response.setContentType("text/html;charset=utf-8");
    			response.getWriter().println("<script language=\"javascript\">alert(\"您还没有登录，请先登录!\");"
    					+ "if(window.opener==null){window.top.location.href=\"../login.jsp\";}"
    					+ "else{window.opener.top.location.href=\"../login.jsp\";window.close();}</script>"); 
    	        response.getWriter().flush();
    	        response.getWriter().close();
    		}else {
        //登录
    			chain.doFilter(request, response);
    		}
    	}
    
    	/**
    	 * @see Filter#init(FilterConfig)
    	 */
    	public void init(FilterConfig fConfig) throws ServletException {
        
    		// TODO Auto-generated method stub
    	}
    }

## AuthFilter ##

package com.scm.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 com.scm.model.User;
    import com.scm.service.AuthService;
    
    /**
     * Servlet Filter implementation class AuthFilter
     */
    @WebFilter("/AuthFilter")
    public class AuthFilter implements Filter {
        
        /**
         * Default constructor. 
         */
        public AuthFilter() {
        
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see Filter#destroy()
    	 */
    	public void destroy() {
        
    		// TODO Auto-generated method stub
    	}
    
    	/**
    	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
    	 */
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        
    		HttpServletRequest req=(HttpServletRequest) request;
    		String path=req.getServletPath();
    		User user=(User) req.getSession().getAttribute("user");
    		boolean flag=new AuthService().authCheck(path, user.getModelUri());
    		if(flag) {
        
    			chain.doFilter(request, response);
    		}else {
        
    			response.getWriter().println("<script language=\"javascript\">alert(\"您还没有权限！\");</script>");
    			response.getWriter().flush();
    			response.getWriter().close();
    		}
    	}
    
    	/**
    	 * @see Filter#init(FilterConfig)
    	 */
    	public void init(FilterConfig fConfig) throws ServletException {
        
    		// TODO Auto-generated method stub
    	}
    }

package com.scm.service;
    
    import java.util.ArrayList;
    
    public class AuthService {
        
    	/**
    	 * 根据servlet路径和user modeluri判断其是否具有权限
    	 * @param path
    	 * @param modelUri
    	 * @return
    	 */
    	public boolean authCheck(String path,ArrayList<String> modelUri) {
        
    		for(String s:modelUri) {
        
    			if(path.startsWith(s)) {
        
    				return true;
    			}
    		}
    		return false;
    	}
    }