ssm和shiro整合，shiro的自定义的realm不能自动注入的问题

在自定义realm的时候注入的时候就会报错，去掉注解@Autowired 运行就会没有问题。错误的原因应该在于注解无法注入

1. @Autowired
2. private UserService userService;
3. // 设置realm的名称
4. @Override
5. public void setName(String name) {
6. super.setName("customRealm");
7. }

这是eclipse报的异常情况。

1. org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'shiroFilter' defined in
2. class path resource [spring-shiro/spring-shiro.xml]:
3. Cannot resolve reference to bean 'securityManager' 
4. while setting bean property 'securityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: 
5. Error creating bean with name 'securityManager' defined in class path resource [spring-shiro/spring-shiro.xml]:
6. Cannot resolve reference to bean 'myRealm' while setting bean property 'realm'; 
7. nested exception is org.springframework.beans.factory.BeanCreationException: 
8. Error creating bean with name 'myRealm':
9. Injection of autowired dependencies failed; 
10. nested exception is org.springframework.beans.factory.BeanCreationException: 
11. Could not autowire field: private com.englishload.service.UserService com.englishload.realm.MyRealm.userService; 
12. nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type
13. [com.englishload.service.UserService]
14. found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. 
15. Dependency annotations: 
16. {@org.springframework.beans.factory.annotation.Autowired(required=true)}

解决方案： 

因为shiro的realm属于Filter,简单说就是初始化realm时, spring 还未加载相关业务Bean,那么解决办法就是将springmvc的配置文件加载提前。

这是改变后的代码，将SpringMVC的配置文件在 <context-param>中加载。

2. <!-- spring mybatis配置 和shiro-->
3. <context-param>
4. <param-name>contextConfigLocation</param-name>
5. <param-value>classpath:spring-mybatis/spring-mybatis.xml,
6. classpath:spring-shiro/spring-shiro.xml,
7. classpath:/springmvc-servlet/springmvc-servlet.xml
8. </param-value>
9. </context-param>
12. <!-- springmvc的配置 -->
13. <servlet>
14. <servlet-name>springmvc</servlet-name>
15. <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
16. <init-param>
17. <param-name>contextConfigLocation</param-name>
18. <param-value>classpath:/springmvc-servlet/springmvc-servlet.xml</param-value>
19. </init-param>
20. <load-on-startup>1</load-on-startup>
21. </servlet>
22. <servlet-mapping>
23. <servlet-name>springmvc</servlet-name>
24. <url-pattern>/</url-pattern>
25. </servlet-mapping>
27. <!-- shiro的filter -->
28. <!-- shiro过虑器，DelegatingFilterProxy通过代理模式将spring容器中的bean和filter关联起来 -->