I'm having a bad time trying to run my program using Spring @Autowired
annotation. Just to explain you what I'm trying to do, I have a main controller class, MainController
, that always uses two other classes ( SquadraController
class and UserController
class) to do some work.
Instead of instantiating these classes any time I need them, I decided to declare them as instance variables with the @Autowired
annotation and call them any time I need them.
So I have my instance variables with @Autowired annotation and declared the beans in the context xml file, but I get the following error and I can't get out of it:
20/03/2015 15:10:00 - WARN - (AbstractApplicationContext.java:487) - Exception encountered during context initialization - cancelling refresh attempt
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.fabrizio.fantavalcanneto.controller.UserController org.fabrizio.fantavalcanneto.controller.MainController.userController; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.fabrizio.fantavalcanneto.controller.UserController] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1204)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:538)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:229)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:725)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
This is my MainController class (the snippet that raises the error):
@Controller
public class MainController {
private static final Logger logger = LoggerFactory.getLogger(MainController.class);
@Autowired
private UserController userController;
@Autowired
private SquadraController squadraController;
This is the xml file where I declare my beans (I also tried to declare MainController bean without declaring the instance variables as properties):
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd">
<context:component-scan base-package="org.fabrizio.fantavalcanneto.controller" />
<bean id="viewResolver"
class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass"
value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/WEB-INF/views/" />
<property name="suffix" value=".jsp" />
</bean>
<bean
class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor"/>
<bean id="userController" class="org.fabrizio.fantavalcanneto.controller.UserController" >
</bean>
<bean id="mainController" class="org.fabrizio.fantavalcanneto.controller.MainController">
<property name="userController" value="userController"></property>
<property name="squadraController" value="squadraController"></property>
</bean>
<bean id="squadraController" class="org.fabrizio.fantavalcanneto.controller.SquadraController">
</bean>
</beans>
UserController
and SquadraController
have no instance variables.
If you are context component scanning you don't need to define the beans in the config file, something like this will work. All you need is @Controller annoation on the relevant classes :
<context:component-scan base-package="org.fabrizio.fantavalcanneto.controller" />
// for default converters etc add this aswell
<mvc:annotation-driven/>
Just check you have the correct base package/typos
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