Shulou(Shulou.com)06/02 Report--

I believe many inexperienced people don't know what to do about how to write the code for springboot filters, interceptors and listeners. Therefore, this article summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

Simple springboot filter, interceptor, listener use

Pom.xml

4.0.0

Sp

Spboot

0.0.1-SNAPSHOT

Org.springframework.boot

Spring-boot-starter-parent

2.0.4.RELEASE

Org.springframework.boot

Spring-boot-starter-web

Org.springframework.boot

Spring-boot-maven-plugin

Filter, servlet3 specification used

Package com.soft.m

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 org.slf4j.Logger

Import org.slf4j.LoggerFactory

Import org.springframework.stereotype.Component

@ WebFilter (filterName= "MyFilter", urlPatterns= "/ *")

Public class MyFilter implements Filter {

Private static Logger LOG = LoggerFactory.getLogger (MyFilter.class)

Public void init (FilterConfig filterConfig) throws ServletException {

LOG.info ("initialize filter")

}

Public void doFilter (ServletRequest request, ServletResponse response, FilterChain chain)

Throws IOException, ServletException {

HttpServletRequest req = (HttpServletRequest) request

String requestURI = req.getRequestURI ()

LOG.info ("filtered request->" + requestURI)

Chain.doFilter (request, response)

}

Public void destroy () {

LOG.info ("destroy filter")

}

}

Listeners are also servlet specifications

ServletContextListener snooping

Package com.soft.m

Import javax.servlet.ServletContextEvent

Import javax.servlet.ServletContextListener

Import javax.servlet.annotation.WebListener

Import org.slf4j.Logger

Import org.slf4j.LoggerFactory

Import org.springframework.boot.web.servlet.ServletComponentScan

Import org.springframework.stereotype.Component

@ Component

@ WebListener ("WebListener")

@ ServletComponentScan ("com.soft.m")

Public class MyListener implements ServletContextListener {

Private static Logger LOG = LoggerFactory.getLogger (MyListener.class)

Public void contextInitialized (ServletContextEvent sce) {

LOG.info ("init:" + sce.getSource (). GetClass (). ToString ())

}

Public void contextDestroyed (ServletContextEvent sce) {

/ / TODO Auto-generated method stub

LOG.info ("contextDestroyed")

}

}

Session listener

Package com.soft.m

Import javax.servlet.annotation.WebListener

Import javax.servlet.http.HttpSessionEvent

Import javax.servlet.http.HttpSessionListener

Import org.slf4j.Logger

Import org.slf4j.LoggerFactory

@ WebListener

Public class MySessionListener implements HttpSessionListener {

Private static Logger LOG = LoggerFactory.getLogger (MySessionListener.class)

Public void sessionCreated (HttpSessionEvent se) {

LOG.info ("sessionCreated:" + se.getSession () .getId ())

}

Public void sessionDestroyed (HttpSessionEvent se) {

LOG.info ("sessionDestroyed:" + se.getSession () .getId ())

}

}

Servlet interceptor

Package com.soft.m

Import javax.servlet.http.HttpServletRequest

Import javax.servlet.http.HttpServletResponse

Import org.slf4j.Logger

Import org.slf4j.LoggerFactory

Import org.springframework.web.method.HandlerMethod

Import org.springframework.web.servlet.HandlerInterceptor

Import org.springframework.web.servlet.ModelAndView

Public class MyInterceptor implements HandlerInterceptor {

Private static Logger logger = LoggerFactory.getLogger (MyFilter.class)

Public boolean preHandle (HttpServletRequest request, HttpServletResponse response, Object handler)

Throws Exception {

HandlerMethod m = (HandlerMethod) handler

Logger.info ("preHandle:" + m.getBeanType () .toString ())

Return true

}

Public void postHandle (HttpServletRequest request, HttpServletResponse response, Object handler

ModelAndView modelAndView) throws Exception {

/ / TODO Auto-generated method stub

Logger.info ("postHandle")

}

Public void afterCompletion (HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)

Throws Exception {

Logger.info ("afterCompletion")

}

}

Intercept configuration

Package com.soft.m

Import org.springframework.context.annotation.Configuration

Import org.springframework.web.servlet.config.annotation.InterceptorRegistry

Import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry

Import org.springframework.web.servlet.config.annotation.WebMvcConfigurer

@ Configuration

Public class MyWebMvcConfigurerAdapter implements WebMvcConfigurer {

Public void addInterceptors (InterceptorRegistry registry) {

/ / TODO Auto-generated method stub

Registry.addInterceptor (new MyInterceptor ()) .addPathPatterns ("/ *")

}

Public void addResourceHandlers (ResourceHandlerRegistry registry) {

/ / registry.addResourceHandler ("/ * .ico")

}

}

Classes started by springboot

Package com.soft.m

Import org.springframework.boot.SpringApplication

Import org.springframework.boot.autoconfigure.SpringBootApplication

@ SpringBootApplication

Public class MApplication {

Public static void main (String [] args) {

SpringApplication.run (MApplication.class, args)

}

}

Controler class example

Package com.soft.m

Import javax.servlet.http.HttpServletRequest

Import org.springframework.stereotype.Controller

Import org.springframework.web.bind.annotation.RequestMapping

Import org.springframework.web.bind.annotation.ResponseBody

@ Controller

@ ResponseBody

Public class HelloController {

@ RequestMapping ("/ hello")

Public String hello () {

Return "hello method in HelloController"

}

@ RequestMapping ("/ create")

Public String create (HttpServletRequest request) {

Request.getSession () .setAttribute ("aaa")

Return "create method in HelloController"

}

@ RequestMapping ("/ destory")

Public String destory (HttpServletRequest request) {

Request.getSession () .invalidate ()

Return "destory method in HelloController"

}

}

After reading the above, have you mastered how to write the code for springboot filters and interceptors and listeners? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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