使用@Autowired时，将基元属性注入Springbean

Question

尝试通过Spring 注入以下内容的myInt

public class MyBean {
@Resource (name="myValue")
private int myInt;

知道吗？我得到了以下职位。但它对我不起作用。我仍然收到以下错误消息。

Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'myValue' must be of type [int], but was actually of type [java.lang.Integer]

详细信息：

下面是我为这个测试创建的测试servlet。

@WebServlet("/myTestServlet")
public class myTestServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public myTestServlet() {
    super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doProcess(request);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doProcess(request);
}
private void doProcess(HttpServletRequest request)
{
    WebApplicationContext applicationContext =
    WebApplicationContextUtils.getWebApplicationContext(
        ((HttpServletRequest) request).getSession().getServletContext());
    MyService service = applicationContext.getBean(MyService.class);
    service.doPrint();
}
}

下面是我用于此测试的服务bean。

public class MyService {
//  @Autowired
//  @Qualifier("myValue")

@Resource (name="myValue")
private int myInt;
public void doPrint ()
{
    System.out.println("myInt is " + myInt);
}
}

以下是我正在使用的applicationContext.xml

<context:annotation-config />
<bean id="myService" class="tsttst.MyService" >
</bean>
<!-- Global configuration -->
<bean id="myValue" class="java.lang.Integer" factory-method="valueOf">
    <constructor-arg value="1000" />
</bean>

以下是我在使用@Resource 时遇到的错误

Caused by: org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'myValue' must be of type [int], but was actually of type [java.lang.Integer]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:349)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:435)
    at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:409)
    at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$ResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:541)
    at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:147)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessPropertyValues(CommonAnnotationBeanPostProcessor.java:297)
    ... 21 more

但是，如果我使用@Autowired，则将产生以下错误

Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private int tsttst.MyService.myInt; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [int] 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), @org.springframework.beans.factory.annotation.Qualifier(value=myValue)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:507)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:283)
    ... 21 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [int] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=myValue)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:914)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:783)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:697)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:478)
    ... 23 more

Answer 1

如何定义int？

如果它是属性（例如带有占位符配置器），则可以使用@Value。

如果它是用带有构造函数arg或工厂方法的<bean id="myValue" class="java.lang.Integer">..</bean>定义的，那么@Autowired/@Resource应该可以工作。

至于自动开箱，它似乎不起作用，所以你需要一个Integer
您也可以尝试<util:constant .. />