java - Spring在非常简单的程序中忽略@Qualifier

Question

我有 Circle 类:

public class Circle
{
    @Autowired
    @Qualifier("pointA")
    private Point center;

    public Point getCenter()
    {
        return center;
    }
    public void setCenter(Point center)
    {
        this.center = center;
    }
}

积分等级:

public class Point
{
    private int x;
    private int y;

    public int getX()
    {
        return x;
    }
    public void setX(int x)
    {
        this.x = x;
    }
    public int getY()
    {
        return y;
    }
    public void setY(int y)
    {
        this.y = y;
    }
}

还有我的 spring xml:

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd"
        >

       <bean id="pointA"  name="pointA" class="SpringTest.Point">
            <qualifier value="pointA"/>
            <property name="x" value="4"/>
            <property name="y" value="4"/>
       </bean>

       <bean id="pointB" name="pointB" class="SpringTest.Point">
              <property name="x" value="2"/>
              <property name="y" value="5"/>
       </bean>

       <bean id="circle" class="SpringTest.Circle">
       </bean>

       <bean class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />

</beans>

就我而言，这应该是这样工作的: 1、Spring看@Autowire注解 2、spring实现Point类型的bean有很多 3、Spring使用@Qualifier注解来决定注入(inject)哪个bean

不幸的是，它不是那样工作的。 执行时:

AbstractApplicationContext abstractApplicationContext = new ClassPathXmlApplicationContext("spring.xml");
BeanFactory beanFactory = abstractApplicationContext.getBeanFactory();

我收到一个错误:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'circle': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private SpringTest.Point SpringTest.Circle.center; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [SpringTest.Point] is defined: expected single matching bean but found 2: pointA,pointB

我是 spring 主题的初学者，但我相信 @Qualifier 注释应该完成这项工作并确定使用哪个 bean。

启动日志: https://gist.github.com/mmajews/384207ee97b2cc8bd49a

Answer 1

您需要添加 <context:annotation-config/>在你的 spring xml 中，而不是实例化 AutowiredAnnotationBeanPostProcessor ，因为它不处理 @Qualifier注释。

或者，如果您真的想控制在上下文中实例化的所有内容，请查看实际的 candidate resolver对于 @Qualifier .