Spring Boot 定义过滤器、监听器、拦截器

时间 2019-11-07

原文原文链接

1、自定义过滤器java

建立一个过滤器，实现javax.servlet.Filter接口，并重写其中的init、doFilter、destory方法。web

[java] view plain copy
package com.example.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;
/**
* 实现javax.servlet.Filter,覆盖其三个方法
* @author Administrator
*
*/
@WebFilter(filterName="customFilter",urlPatterns="/*")
public class CustomFilter implements Filter{

@Override
public void destroy() {
System.out.println("CustomFilter过滤器销毁");
}

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
System.out.println("CustomFilter指定过滤器操做......");
//执行操做后必须doFilter
chain.doFilter(request, response);
}

@Override
public void init(FilterConfig arg0) throws ServletException {
System.out.println("CustomFilter初始化......");
}
}
2、自定义监听器spring

建立一个过滤器，实现ServletContextListener接口session

[java] view plain copy
package com.example.listener;

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

/**
* 实现ServletContextListener，覆盖其两个方法
* @author Administrator
*
*/
@WebListener
public class CustomListener implements ServletContextListener{

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

@Override
public void contextInitialized(ServletContextEvent servletContext) {
System.out.println("servletContext初始化......");
}
} ide

建立一个session监听器，监听session的建立和销毁
[java] view plain copy
package com.example.listener;

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

/**
* 实现HttpSessionListener接口，监视session的动态
* @author Administrator
*
*/
@WebListener
public class SessionListener implements HttpSessionListener{

@Override
public void sessionCreated(HttpSessionEvent session) {
System.out.println("session建立成功......");
}

@Override
public void sessionDestroyed(HttpSessionEvent session) {
System.out.println("session销毁......");
}
}
3、自定义拦截器post

步骤：url

一、建立本身的拦截器实现HandlerInterceptor接口spa

二、建立本身的拦截器链，继承WebMvcConfigurerAdapter类，重写addInterceptors方法。.net

三、实例化本身的拦截器，并加入到拦截器链中。继承

拦截器一：

[java] view plain copy
package com.example.Interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class CustomInterceptor implements HandlerInterceptor {

@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object object,
Exception exception) throws Exception {
//在整个请求结束以后被调用，也就是在DispatcherServlet 渲染了对应的视图以后执行（主要是用于进行资源清理工做）
System.out.println("3. 整个请求结束以后被调用......CustomInterceptor1......");
}

@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object object, ModelAndView view)
throws Exception {
// 请求处理以后进行调用，可是在视图被渲染以前
System.out.println("2. 请求处理以后进行调用，可是在视图被渲染以前......CustomInterceptor1......");
}

@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object object) throws Exception {
// 在请求处理以前进行调用
System.out.println("1. 在请求处理以前进行调用......CustomInterceptor1......");
// 只有返回true才会继续向下执行，返回false取消当前请求
return true;
}
}

拦截器二：
[java] view plain copy
package com.example.Interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class CustomInterceptor2 implements HandlerInterceptor {

@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object object,
Exception exception) throws Exception {
//在整个请求结束以后被调用，也就是在DispatcherServlet 渲染了对应的视图以后执行（主要是用于进行资源清理工做）
System.out.println("3. 整个请求结束以后被调用......CustomInterceptor2......");
}

@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object object, ModelAndView view)
throws Exception {
// 请求处理以后进行调用，可是在视图被渲染以前
System.out.println("2. 请求处理以后进行调用，可是在视图被渲染以前......CustomInterceptor2......");
}

@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object object) throws Exception {
// 在请求处理以前进行调用
System.out.println("1. 在请求处理以前进行调用......CustomInterceptor2......");
// 只有返回true才会继续向下执行，返回false取消当前请求
return true;
}
}

自定义拦截器链并加入自定义的拦截器 [java] view plain copy package com.example.adapter; import org.springframework.context.annotation.Configuration; import org.springframework.web.servlet.config.annotation.InterceptorRegistry; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; import com.example.Interceptor.CustomInterceptor; import com.example.Interceptor.CustomInterceptor2; /** * 继承WebMvcConfigurerAdapter，复写addInterceptors方法 * @author Administrator * */ @Configuration public class WebAdapter extends WebMvcConfigurerAdapter{ @Override public void addInterceptors(InterceptorRegistry registry) { //众多的拦截器组成了一个拦截器链 /** * 主要方法说明： * addPathPatterns 用于添加拦截规则 * excludePathPatterns 用户排除拦截 */ registry.addInterceptor(new CustomInterceptor()).addPathPatterns("/*"); registry.addInterceptor(new CustomInterceptor2()).addPathPatterns("/*"); super.addInterceptors(registry); } }