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Springboot引入拦截器

自定义的拦截器类 Interceptor

package cn.zytao.taosir.auth.config;

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

public class AuthInterceptor implements HandlerInterceptor{
    
    /**
     * 请求处理之后
     */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        // TODO Auto-generated method stub
        HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
    }

    /**
     * 请求处理之后调用
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
        // TODO Auto-generated method stub
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }

    /**
     * 请求处理之前
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        return HandlerInterceptor.super.preHandle(request, response, handler);
    }
}

将拦截器添加到springmvc配置中，并放行swagger的相关资源

package cn.zytao.taosir.auth.config;

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.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;

@Configuration
public class SpringMVCConfig extends WebMvcConfigurationSupport{

    @Bean
    public AuthInterceptor getAuthInterceptor() {
        return new AuthInterceptor();
    }


    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry
        .addInterceptor(getAuthInterceptor())
        .addPathPatterns("/**")
        .excludePathPatterns("/login")
        .excludePathPatterns("/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**");
        super.addInterceptors(registry);
    }

    @Override
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("swagger-ui.html")
        .addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**")
        .addResourceLocations("classpath:/META-INF/resources/webjars/");
        super.addResourceHandlers(registry);
    }
}

在addInterceptors方法中添加拦截器时，是new的一个拦截器。而并不是引入springBean容器初始化时，已经初始化好了的bean实例，并不是同一个对象，故而访问时肯定是无法引入Interceptor类里面引入的bean实例，可能产生空指针异常。即无法引入默认注入的Bean，那么我们就自己定义一个Bean，然后在拦截器添加方法内引入这个bean即可，上面主要对此进行了处理。