springboot-11-servlet, listener, fitlter的添加

springboot中添加servlet, filter, listener有2种方式: 代码注册servlet 和自动注解注册(在使用druid监控有使用过)

代码注册通过ServletRegistrationBean、 FilterRegistrationBean 和 ServletListenerRegistrationBean 获得控制。也可以通过servletContextInitializer接口直接注册

在 SpringBootApplication 上使用@ServletComponentScan注解后，Servlet、Filter、Listener 可以直接通过 @WebServlet、@WebFilter、@WebListener 注解自动注册，无需其他代码。

编写测试类:

Servlet:

1), 使用代码注册的方式

package com.iwhere.test.web.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 通过代码注册servlet
 * 代码注册通过ServletRegistrationBean、 FilterRegistrationBean 和 ServletListenerRegistrationBean 获得控制。 
    也可以通过实现 ServletContextInitializer 接口直接注册。
 * @author wenbronk
 * @time 2017年3月17日  下午2:23:21  2017
 */

public class MyServlet extends HttpServlet {
    private static final long serialVersionUID = 6272693061640286219L;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//        super.doGet(req, resp);
        System.out.println("method deGet is run");
        doPost(req, resp);
    }
    
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//        super.doPost(req, resp);
        System.out.println("method doPost is run");
        
        resp.setContentType("text/html"); 
        PrintWriter out = resp.getWriter(); 
        out.println("<html>"); 
        out.println("<head>"); 
        out.println("<title>Hello World</title>"); 
        out.println("</head>"); 
        out.println("<body>"); 
        out.println("<h1>这是：MyServlet1</h1>"); 
        out.println("</body>"); 
        out.println("</html>");
    }
    
}

然后在 App.java (或者任意一类中, 该类必须@component被spring管理)

    /**
     * 使用代码注册Servlet
     * 此方法不需要加注解  @ServletComponentScan
     * @return
     */
    @Bean
    public ServletRegistrationBean myServlet() {
         return new ServletRegistrationBean(new MyServlet(),"/myServlet/*");
    }

2), 使用注解的方式实现:

package com.iwhere.test.web.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 使用注解的方式注册servlet
 * 
 * @author wenbronk
 * @time 2017年3月17日 下午4:10:33 2017
 */

@WebServlet(urlPatterns = "/myServlet2/*", description = "Servlet注解方式")
public class AnnotionServlet extends HttpServlet {
    private static final long serialVersionUID = 1121465382990088487L;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//        super.doGet(req, resp);
        System.err.println("do Get");
        doPost(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//        super.doPost(req, resp);
        System.err.println("do post");

        resp.setContentType("text/html");
        PrintWriter out = resp.getWriter();
        out.println("<html>");
        out.println("<head>");
        out.println("<title>Hello World</title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h1>这是：myServlet2</h1>");
        out.println("</body>");
        out.println("</html>");
    }

}

测试: 可通过http://localhost:8080/springboot-learn/myServlet进行访问: (有加context配置)

Filter的配置:

此处只讲注解方式, 代码方式和servlet一样

package com.iwhere.test.web.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;

/**
 * 使用注解的方式创建filter, 实现一个filter接口
 * 必须加注解@ServletComponentScan
 * @author wenbronk
 * @time 2017年3月17日  下午4:48:19  2017
 */

@WebFilter(filterName="myFilter", urlPatterns="/*")
public class MyFilter implements Filter {

    @Override
    public void destroy() {
        System.out.println("filter is destroy");
    }

    @Override
    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
            throws IOException, ServletException {
        System.out.println("running filter");
        arg2.doFilter(arg0, arg1);
    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {
        System.out.println("filter is init");
    }

    
}

之后必须在main类上添加包扫描或者指定类

@SpringBootApplication
@EnableScheduling
@EnableTransactionManagement(proxyTargetClass = true)
@ServletComponentScan(basePackageClasses = {com.binfo.sqgf.config.SqlInjectFilter.class})
public class SqgfApplication {

或者

@SpringBootApplication

@EnableAutoConfiguration
@EnableWebMvc
@ServletComponentScan(basePackages = "com.fanyin.eghm")
public class EghmApplication {

    public static void main(String[] args) {
        SpringApplication.run(EghmApplication.class, args);
    }
}

listener

listener有contextListener, sessionListener,pageListener, beanListener 好多种

servletContextListener;

package com.iwhere.test.web.listener;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;

/**
 * 使用注解的方式实现Contextlistener, 必须实现listener接口
 * 
 * @author wenbronk
 * @time 2017年3月17日  下午4:51:24  2017
 */
@WebListener
public class MyListener implements ServletContextListener{

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        System.out.println("servletContext destroyed");
    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        System.out.println("servletContext init");
    }

}

sessionListener

package com.iwhere.test.web.listener;

import javax.servlet.annotation.WebListener;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;

/**
 * sessionListener, 监听session的创建和销毁
 * @author wenbronk
 * @time 2017年3月17日  下午4:56:22  2017
 */
@WebListener
public class MySessionListener implements HttpSessionListener {

    @Override
    public void sessionCreated(HttpSessionEvent arg0) {
        System.out.println("HttpSession created");
    }

    @Override
    public void sessionDestroyed(HttpSessionEvent arg0) {
        System.out.println("HttpSession destroyed");
        
    }

}

补充一点, 在listener中使用 springboot的工厂

mongoTemplate = WebApplicationContextUtils.getWebApplicationContext(sce.getServletContext()).getBean(MongoTemplate.class);