Question

我有两个类Student和Address，它们分别实现了IStudent和IAddress接口。 Student类与Address类有关系。这就是我宣布它的参考成员的原因。

public class Student implements IStudent {

    private String code;
    private String name;

    @Autowired
    private IAddress address;

    @Override
    public String getCode() {
        return this.code;
    }

    @Override
    public String getName() {
        return this.name;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public void setName(String name) {
        this.name = name;
    }


    public IAddress getAddress() {
        return this.address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }


}

我有地址类

public class Address implements IAddress{

    private String city;
    private String pinCode;
    private String houseNo;
    private String roadName;
    @Override
    public String getCity() {
        return this.city;
    }

    @Override
    public String getPinCode() {
        return this.pinCode;
    }

    @Override
    public String getHouseNo() {
        return this.houseNo;
    }

    @Override
    public String getRoadName() {
        return this.roadName;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public void setPinCode(String pinCode) {
        this.pinCode = pinCode;
    }

    public void setHouseNo(String houseNo) {
        this.houseNo = houseNo;
    }

    public void setRoadName(String roadName) {
        this.roadName = roadName;
    }


}

在我的applicationContext.xml文件中，我编写了以下bean定义

<?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"  
    xsi:schemaLocation="http://www.springframework.org/schema/beans  
               http://www.springframework.org/schema/beans/spring-beans-4.0.xsd">  
    <bean id="studentbean" class="main.Student">  
        <property name="code" value="S001"></property>  
        <property name="name" value="Subhabrata Mondal"></property>  

    </bean>  

    <bean id="addressbean" class="main.Address">  
        <property name="houseNo" value="119/2"></property>  
        <property name="roadName" value="South Avenue"></property>  
        <property name="city" value="Delhi"></property>  
        <property name="pinCode" value="110005"></property>  
    </bean>  

</beans>

当我在初始化bean之后检查了Student对象时，名称和代码已经使用setter方法分配。但是地址没有分配。因此它显示地址的空值。我用@Autowired注释标记了地址。你能帮忙吗？

 ApplicationContext factory = new ClassPathXmlApplicationContext("applicationContext.xml");
        Student student = (Student) factory.getBean("studentbean");
        System.out.println(student.getAddress());

Answer 1

您需要明确连接到Address not IAddress，因为CI只知道地址，如果您要连线

  @Autowired
   private Address address;

或者你需要定义一个带有IAddress类型的bean，但是确保你没有多个实现，或者spring会混淆，如果你有多个实现使用可以使用限定符来清除歧义

Answer 2

这整个例子有点奇怪但是你可以摆脱@Autowired注释并使用下面的bean配置;

<bean id="studentbean" class="main.Student">  
        <property name="code" value="S001"></property>  
        <property name="name" value="Subhabrata Mondal"></property>  
        <property name="address" >
            <ref local="addressbean"/>
        </property> 
</bean>

地址值显示为null

2 个答案: