package com.rskd_yswb.lib.filter;

import javax.servlet.*;

import java.io.IOException;

public class HttpRequestAndResponseFilter implements Filter {

    private FilterConfig filterConfig;

    public void destroy() {

    }

    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {

        resp.setCharacterEncoding(this.filterConfig.getInitParameter("encoding"));

        System.out.println("HttpRequestAndResponseFilterBefore");

        chain.doFilter(req, resp);

        System.out.println("HttpRequestAndResponseFilterAfter");

    }

    public void init(FilterConfig config) throws ServletException {

        this.filterConfig = config;

    }

}

package com.rskd_yswb.lib.filter;

import javax.servlet.*;

import java.io.IOException;

public class Test2Filter implements Filter {

    public void destroy() {

    }

    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {

        System.out.println("Test2FilterBefore");

        chain.doFilter(req, resp);

        System.out.println("Test2FilterAfter");

    }

    public void init(FilterConfig config) throws ServletException {

    }

}

package com.rskd_yswb.servelt;

import com.rskd_yswb.javabean.db.ConsumerEntity;

import com.rskd_yswb.lib.db.DBConnection;

import com.rskd_yswb.lib.db.GenerateSqlStatement;

import com.rskd_yswb.lib.freemarker.FreeMarker;

import freemarker.template.Template;

import freemarker.template.TemplateException;

import org.apache.commons.dbutils.QueryRunner;

import org.apache.commons.dbutils.handlers.BeanMapHandler;

import org.apache.logging.log4j.LogManager;

import org.apache.logging.log4j.Logger;

import javax.servlet.annotation.WebServlet;

import java.io.IOException;

import java.io.Writer;

import java.sql.Connection;

import java.util.HashMap;

import java.util.Map;

public class IndexServlet extends javax.servlet.http.HttpServlet {

    private static Logger logger = LogManager.getLogger(IndexServlet.class);

    protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {

        doGet(request, response);

    }

    protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {

        String sql = new GenerateSqlStatement().select("*").from("consumer").get();

        try {

            Map<String, ConsumerEntity> consumer = new QueryRunner().query(DBConnection.getConnection(), sql, new BeanMapHandler<String, ConsumerEntity>(ConsumerEntity.class, "username"));

        } catch (Exception e) {

            logger.debug("IndexServlet Error:" + e.getMessage());

        }

        Map<String, Object> root = new HashMap<String, Object>();

        try {

            FreeMarker.getFreemarker().getTemplate("index.ftl").process(root, response.getWriter());

            System.out.println("请求处理中");

        } catch (TemplateException e) {

            logger.debug("IndexServlet Error:" + e.getMessage());

        }

    }

}

<web-app>

    <filter>

        <filter-name>HttpRequestAndResponseFilter</filter-name>

        <filter-class>com.rskd_yswb.lib.filter.HttpRequestAndResponseFilter</filter-class>

        <init-param>

            <param-name>encoding</param-name>

            <param-value>utf8</param-value>

        </init-param>

    </filter>

    <filter>

        <filter-name>Test2Filter</filter-name>

        <filter-class>com.rskd_yswb.lib.filter.Test2Filter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>HttpRequestAndResponseFilter</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

    <filter-mapping>

        <filter-name>Test2Filter</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

    <servlet>

        <servlet-name>IndexServlet</servlet-name>

        <servlet-class>com.rskd_yswb.servelt.IndexServlet</servlet-class>

    </servlet>

    <servlet-mapping>

        <servlet-name>IndexServlet</servlet-name>

        <url-pattern>/index</url-pattern>

    </servlet-mapping>

    <servlet-mapping>

        <servlet-name>IndexServlet</servlet-name>

        <url-pattern></url-pattern>

    </servlet-mapping>

</web-app>

HttpRequestAndResponseFilterBefore

Test2FilterBefore

请求处理中

Test2FilterAfter

HttpRequestAndResponseFilterAfter