java - 引用另一个 .xml 中定义的 bean

Question

我有 2 个 Spring 应用程序上下文 XML:

A.xml

<bean id="aBean" class="...">
    <constructor-arg name="..." ref="..."/>
    <constructor-arg name="bBean" value="#{getObject('bBean')}"/>
</bean>

B.xml

 <bean id="bBean" class="...">
    ...
 </bean>

<import resource="classpath*:A.xml" />

文件 A.xml 不受我的控制，因此我无法使用 <import resource="classpath*:B.xml" /> 导入 B.xml ，但是 B.xml 导入 A.xml，所以情况正好相反。

由于许可 SpEL，aBean 始终以 bBean 实例化为空。语法#{getObject('bBean')} 。

有办法克服这个问题吗？

谢谢!

Answer 1

这有效:

主类:

package com.example;

import com.example.route.A;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.ImportResource;


@SpringBootApplication
@ImportResource(locations = {"classpath*:/ctxt/B.xml"})
public class DemoApplication {


    public static void main(String[] args) {
        ApplicationContext ctxt = SpringApplication.run(DemoApplication.class, args);

        A a = ctxt.getBean(A.class);
        System.out.println(a.toString());   // A{b=com.example.route.B@5488b5c5}   <-- A init correctly with non-null B


    }
}

A 类:

package com.example.route;

public class A {

    private B b;

    public A(B b) {
        this.b = b;
    }

    public B getB() {
        return b;
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder("A{");
        sb.append("b=").append(b);
        sb.append('}');
        return sb.toString();
    }
}

B 类:

package com.example.route;

public class B {
}

/resources/ctxt/A.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="aBean" class="com.example.route.A">
        <constructor-arg name="bBean" value="#getObject('bBean')"/>
    </bean>
</beans>

/resources/ctxt/B.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="bBean" class="com.example.route.B"></bean>

    <import resource="classpath*:ctxt/A.xml"></import>
</beans>