1、定义拦截器
实现 HandlerInterceptor 接口,重写里面重要的三个比较常用的方法
preHandle():在请求处理之前进行调用(Controller方法调用之前)
postHandle():请求处理之后进行调用,但是在视图被渲染之前(Controller方法调用之后)
afterCompletion():在整个请求结束之后被调用,也就是在DispatcherServlet 渲染了对应的视图之后执行(主要是用于进行资源清理工作)
package com.example.demoinitializr.Interceptor;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class TestInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("执行了TestInterceptor的preHandle方法");
String url = request.getRequestURI();
String username = request.getParameter("username");
String password = request.getParameter("password");
String parameter = request.getQueryString();
String token = request.getHeader("token");
System.out.println(parameter);
System.out.println(token);
if(url=="/user/login"){
return true;
}
if(username == "admin" && password == "123456"){
return true;
} else {
}
return HandlerInterceptor.super.preHandle(request, response, handler);
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("执行了TestInterceptor的postHandle方法");
HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("执行了TestInterceptor的afterCompletion方法");
HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
}
}
2、配置拦截器
继承 WebMvcConfigurer 类,并重写其中的方法 addInterceptors,在主类加上@Configuration在启动的时候在会被加载
package com.example.demoinitializr.config;
import com.example.demoinitializr.Interceptor.TestInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(TestInterceptor()).addPathPatterns("/**");
//注册TestInterceptor拦截器
//InterceptorRegistration registration = registry.addInterceptor(new TestInterceptor());
//registration.addPathPatterns("/**"); //所有路径都被拦截
}
@Bean
public TestInterceptor TestInterceptor() {
return new TestInterceptor();
}
}
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