SpringBoot拦截器

1. 创建一个拦截器实现HandlerInterceptor接口

	package wmq.fly.mybatis.interceptor;
	
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;
	
	import org.springframework.stereotype.Component;
	import org.springframework.web.servlet.HandlerInterceptor;
	import org.springframework.web.servlet.ModelAndView;
	
	@Component
	public class LoginInterceptor implements HandlerInterceptor {
	    /**
	     * 预处理回调方法，实现处理器的预处理
	     * 返回值：true表示继续流程；false表示流程中断，不会继续调用其他的拦截器或处理器
	   */
	    @Override
	    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
	            throws Exception {
	        System.out.println("开始拦截.........");
	        //业务代码
	        return false;
	    }
	
	     /**
	     * 后处理回调方法，实现处理器（controller）的后处理，但在渲染视图之前
	     * 此时我们可以通过modelAndView对模型数据进行处理或对视图进行处理
	     */
	    @Override
	    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
	            ModelAndView modelAndView) throws Exception {
	        // TODO Auto-generated method stub
	
	    }
	    /**
	     * 整个请求处理完毕回调方法，即在视图渲染完毕时回调，
	     * 如性能监控中我们可以在此记录结束时间并输出消耗时间，
	     * 还可以进行一些资源清理，类似于try-catch-finally中的finally，
	     * 但仅调用处理器执行链中
	     */
	    @Override
	    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
	            throws Exception {
	        // TODO Auto-generated method stub
	
	    }
	
	}

2 新建配置类来管理拦截器，并将之前的拦截器注入其中

package wmq.fly.mybatis.interceptor;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;

@Configuration
public class MvcInterceptorConfig extends WebMvcConfigurationSupport{

    @Autowired
    private LoginInterceptor loginInterceptor;

    @Override
    protected void addInterceptors(InterceptorRegistry registry) {
        // 多个拦截器组成一个拦截器链
        // addPathPatterns 用于添加拦截规则，/**表示拦截所有请求
        // excludePathPatterns 用户排除拦截
        registry.addInterceptor(loginInterceptor).addPathPatterns("/**")
        .excludePathPatterns("/stuInfo/getAllStuInfoA","/account/register");    
        super.addInterceptors(registry);
    }
}

二、使用servlet的filter拦截器

	package wmq.fly.mybatis.filter;
	
	import java.io.IOException;
	import java.util.Arrays;
	
	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 javax.servlet.http.HttpServletResponse;
	
	import org.springframework.stereotype.Component;
	
	@Component
	@WebFilter(urlPatterns="/**",filterName="loginFilter")
	public class LoginFilter implements Filter{
	
	    //排除不拦截的url
	    private static final String[] excludePathPatterns = { "/stuInfo/getAllStuInfoA"};
	
	    @Override
	    public void init(FilterConfig filterConfig) throws ServletException {
	        // TODO Auto-generated method stub
	    }
	
	    @Override
	    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
	            throws IOException, ServletException {
	
	        HttpServletRequest req = (HttpServletRequest)request;
	        HttpServletResponse res = (HttpServletResponse)response;
	
	        // 获取请求url地址，不拦截excludePathPatterns中的url
	        String url = req.getRequestURI();
	        if (Arrays.asList(excludePathPatterns).contains(url)) {
	            //放行，相当于第一种方法中LoginInterceptor返回值为true
	            chain.doFilter(request, response);
	        }
	
	        System.out.println("开始拦截了................");
	        //业务代码
	    }
	
	    @Override
	    public void destroy() {
	        // TODO Auto-generated method stub
	    }
	
	}