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);