Fliter 过滤器
请求在到达Controller之前进行与返回去之后 调用 入参为 reuqest,response,chian,过滤器获取不了具体调用哪一个类,哪一个方法。
实现:
1、继承 Filter 接口
import java.io.IOException;
import java.util.Date;
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 org.springframework.stereotype.Component;
//@Component
public class TimeFilter implements Filter{
@Override
public void init(FilterConfig filterConfig) throws ServletException {
System.out.println("TimeFilter init");
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
System.out.println("TimeFilter in");
long startTime = new Date().getTime();
chain.doFilter(request, response);
System.out.println("TimeFilter out 耗时:" + (new Date().getTime() - startTime));
}
@Override
public void destroy() {
System.out.println("TimeFilter destroy");
}
}
2、声明:两种方式,一是在类前加入@Component ,不能指定拦截的路径;二是 对于SSM 在web.xml中进行声明,对于 SpringBoot 在webConfig中声明
web.xml
<filter> <filter-name>encodingFilterfilter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilterfilter-class> <init-param> <param-name>encodingparam-name> <param-value>UTF-8param-value> init-param> filter> <filter-mapping> <filter-name>encodingFilterfilter-name> <url-pattern>/*url-pattern> filter-mapping>
SpringBoot:
package com.maple.web.config;
import java.util.ArrayList;
import java.util.List;import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;import com.maple.web.filter.TimeFilter;
import com.maple.web.interceptor.TimeInterceptor;
@Configuration
public class WebConfig{
@Bean
public FilterRegistrationBean timeFilter() {
FilterRegistrationBean registrationBean = new FilterRegistrationBean();
TimeFilter timeFilter = new TimeFilter();
registrationBean.setFilter(timeFilter);
List url = new ArrayList<>();
url.add("/*");
registrationBean.setUrlPatterns(url);
return registrationBean;
}
}
Interceptor 拦截器
请求在到达Controller之前进行与返回去之后 调用 入参为 reuqest,response,handler,在过滤器之后调用,能够知道调用哪一个类,但是获取不了参数
1、继承HandlerInterceptor ,perHandler 在进入Controller前执行,若返回false则不进入Controller ,true进入Controller ,postHandler处理完Controller后进入此方法,若发生异常,则不进入postHandler。afterCompletion 都会进入此方法,无论是否发生异常都会进入。
package com.maple.web.interceptor;
import java.util.Date;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
/**
* @author hzc
*
*/
@Component
public class TimeInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
System.out.println("preHandle");
System.out.println(((HandlerMethod)handler).getBean().getClass().getName());
System.out.println(((HandlerMethod)handler).getMethod().getName());
request.setAttribute("startTime", new Date().getTime());
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
System.out.println("postHandle");
long startTime = (long) request.getAttribute("startTime");
System.out.println("time interceptor 耗时: " + (new Date().getTime() - startTime));
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
throws Exception {
System.out.println("afterCompletion");
long startTime = (long) request.getAttribute("startTime");
System.out.println("time interceptor 耗时: " + (new Date().getTime() - startTime));
System.out.println("ex is " + ex);
}
}
2、声明,在SSM中需要在spring配置文件中声明,在Springboot中在Config中声明。
SSM:
<mvc:interceptors> <mvc:interceptor> <mvc:mapping path="/**"/> <bean id="userinterceptor" class="org.sz.source.schedul.common.BaseOrgUserInterceptor"> <property name="excludedUrls"> <list> <value>/login.dovalue> list> property> bean> mvc:interceptor> mvc:interceptors>
SpringBoot:
package com.maple.web.config;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
@Configuration
public class WebConfig extends WebMvcConfigurerAdapter{
@Autowired
private TimeInterceptor timeInterceptor;
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(timeInterceptor);
}
}
Aspect 切面
使用切面,可前置增强,后置增强,环绕增强,在拦截器之后执行,可获取参数信息
1、编写切面方法类
import java.util.Date;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
/**
* @author hzc
*
*/
@Aspect
@Component
public class TimeAspect {
@Around("execution(* com.maple.web.controller.UserController.*(..))")
public Object handlerControllerMethod(ProceedingJoinPoint pjp) throws Throwable {
System.out.println("time aspect start");
Object[] args = pjp.getArgs(); // 获取参数
for (Object arg : args) {
System.out.println("arg is " + arg);
}
long startTime = new Date().getTime();
Object object = pjp.proceed();
System.out.println("time aspect 耗时: " + (new Date().getTime() - startTime));
return object;
}
}
Filter、Interceptor、Aspect的作用范围如下:
Original: https://www.cnblogs.com/maple92/p/10781154.html
Author: Topze
Title: Filter、Interceptor、Aspect 区别及实现
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