解决自定义Shiro.Realm扩展类不能用注解（@Resource或@Autowire）自动装配的有关问题

package com.xkt.shiro

import org.apache.shiro.realm.Realm;
import org.apache.shiro.web.mgt.DefaultWebSecurityManager;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.annotation.Configuration;

/**
 * 把securityManager和userRealm装配到ApplicationContext
 */
@Configuration
public class ShiroConfig implements ApplicationContextAware {

    @Override
    public void setApplicationContext(ApplicationContext ac) throws BeansException {
        Realm userRealm = (Realm) ac.getBean("userRealm");
        DefaultWebSecurityManager defaultWebSecurityManager = (DefaultWebSecurityManager) ac.getBean("securityManager");
        defaultWebSecurityManager.setRealm(userRealm);
    }
}