Spring Boot+Shiro拦截登陆返回Json结果（前后

1、自定义访问控制拦截器，继承AccessControlFilter，实现以下三个方法。

    abstract boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) throws Exception;  
    
    boolean onAccessDenied(ServletRequest request, ServletResponse response, Object mappedValue) throws Exception; 
    
    abstract boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception;  

2、自定义BeamUserFilter

package com.hsshy.beam.common.intercept;
import com.hsshy.beam.common.enumeration.RetEnum;
import com.hsshy.beam.common.utils.R;
import com.hsshy.beam.common.utils.RenderUtil;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.web.filter.AccessControlFilter;
import org.apache.shiro.web.util.WebUtils;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;
public class BeamUserFilter extends AccessControlFilter {

    /**
     *
     * 表示是否允许访问；mappedValue就是[urls]配置中拦截器参数部分，如果允许访问返回true，否则false；
     * (感觉这里应该是对白名单（不需要登录的接口）放行的)
     * 如果isAccessAllowed返回true则onAccessDenied方法不会继续执行
     * 这里可以用来判断一些不被通过的链接（个人备注）
     * * 表示是否允许访问 ，如果允许访问返回true，否则false；
     * @param request
     * @param response
     * @param mappedValue 表示写在拦截器中括号里面的字符串 mappedValue 就是 [urls] 配置中拦截器参数部分
     * @return
     * @throws Exception
     * */
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {


        if (isLoginRequest(request, response)) {
            return true;
        } else {
            Subject subject = getSubject(request, response);
            // If principal is not null, then the user is known and should be allowed access.
            return subject.getPrincipal() != null;
        }
    }

    /**
     * 表示当访问拒绝时是否已经处理了；如果返回true表示需要继续处理；如果返回false表示该拦截器实例已经处理了，将直接返回即可。
     * onAccessDenied是否执行取决于isAccessAllowed的值，如果返回true则onAccessDenied不会执行；如果返回false，执行onAccessDenied
     * 如果onAccessDenied也返回false，则直接返回，不会进入请求的方法（只有isAccessAllowed和onAccessDenied的情况下）
     * */
    @Override
    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletResponse httpServletResponse = WebUtils.toHttp(response);
        RenderUtil.renderJson(httpServletResponse, R.fail(RetEnum.LOGIN_EXPIRED.getRet(),RetEnum.LOGIN_EXPIRED.getMsg()));
        return false;

    }
}

3、ShiroConfig配置，加入以下配置

package com.hsshy.beam.config;
import com.hsshy.beam.common.intercept.BeamUserFilter;
import com.hsshy.beam.common.shiro.RedisShiroSessionDAO;
import com.hsshy.beam.common.shiro.UserRealm;
import org.apache.shiro.mgt.SecurityManager;
import org.apache.shiro.session.mgt.SessionManager;
import org.apache.shiro.spring.LifecycleBeanPostProcessor;
import org.apache.shiro.spring.security.interceptor.AuthorizationAttributeSourceAdvisor;
import org.apache.shiro.spring.web.ShiroFilterFactoryBean;
import org.apache.shiro.web.mgt.DefaultWebSecurityManager;
import org.apache.shiro.web.session.mgt.DefaultWebSessionManager;
import org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.servlet.Filter;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
@Configuration
public class ShiroConfig {

  
    @Bean("shiroFilter")
    public ShiroFilterFactoryBean shiroFilter(SecurityManager securityManager) {
        ShiroFilterFactoryBean shiroFilter = new ShiroFilterFactoryBean();
        shiroFilter.setSecurityManager(securityManager);
        shiroFilter.setLoginUrl("/login");
        shiroFilter.setUnauthorizedUrl("/");

        //session过期拦截
        HashMap<String, Filter> myFilters = new HashMap<>();
        myFilters.put("user", new BeamUserFilter());
        shiroFilter.setFilters(myFilters);
        Map<String, String> filterMap = new LinkedHashMap<>();
        /*swagger 资源过滤*/
        filterMap.put("/swagger/**", "anon");
        filterMap.put("/v2/api-docs", "anon");
        filterMap.put("/swagger-ui.html", "anon");
        filterMap.put("/webjars/**", "anon");
        filterMap.put("/swagger-resources/**", "anon");

        filterMap.put("/login/**", "anon"); //登陆
        filterMap.put("/kaptcha", "anon");  //验证码
        filterMap.put("/global/*", "anon");  //全局路径（错误或者超时）
        filterMap.put("/api/**", "anon");

        filterMap.put("/favicon.ico", "anon");
        filterMap.put("/**", "user");
        shiroFilter.setFilterChainDefinitionMap(filterMap);

        return shiroFilter;
    }


  
}