Springboot中使用Interceptor(攔截器)

1.創建自定義的攔截器並實現HandlerInterceptor接口

package com.demo.common.interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class MyInterceptor implements HandlerInterceptor{
    
    Logger logger = LoggerFactory.getLogger(MyInterceptor.class);
    
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        logger.info("preHandle :" +request.getContextPath());
        HttpSession session = request.getSession();
        if (session.getAttribute("user") != null)
            return true;
        // 跳轉登錄
        String url = request.getContextPath() + "/login";
        response.sendRedirect(url);
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
        
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
   
    }
}

2.創建一個java類繼承WebMvcConfiguraeAdapter並重寫addInterceptor方法（該類用來添加配置攔截器在該類中添加配置攔截器，以及配置過濾）

package com.demo.common.interceptor;

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 AddInterceptor extends WebMvcConfigurerAdapter{
    
    public void addInterceptors(InterceptorRegistry registry){
        registry.addInterceptor(new MyInterceptor())
        .addPathPatterns("/**")
        .excludePathPatterns("/login")
        .excludePathPatterns("/loginPost");
    }
}