刚开始跟着视频学习Spring,现遇到下面一个小问题不明白
spring配置文件的片段如下:
<bean id = "car" class ="autowire.Car" p:brand="Aodi" p:price="100000"></bean>
<bean id = "person" class ="autowire.Person" p:name="Mike" p:address-ref="address" p:car-ref="car"></bean>
<bean id = "person2" class ="autowire.Person" p:name="Jack" p:address-ref="address" depends-on="car"></bean>
main测试函数片段如下:
Person person = (Person) ctx.getBean("person");
System.out.println(person);
Person person2 = (Person) ctx.getBean("person2");
System.out.println(person2);
输出结果:
Person [name=Mike, address=Address [city=Beijing, street=Wudaokou], car=Car [brand=Aodi, price=100000.0]]
Person [name=Jack, address=Address [city=Beijing, street=Wudaokou], car=null]
请问一下大家,为什么使用depend-on设置依赖bean的时候,Car对象为空呢?depend-on和ref的有什么区别呢?
spring配置文件的片段如下:
<bean id = "car" class ="autowire.Car" p:brand="Aodi" p:price="100000"></bean>
<bean id = "person" class ="autowire.Person" p:name="Mike" p:address-ref="address" p:car-ref="car"></bean>
<bean id = "person2" class ="autowire.Person" p:name="Jack" p:address-ref="address" depends-on="car"></bean>
main测试函数片段如下:
Person person = (Person) ctx.getBean("person");
System.out.println(person);
Person person2 = (Person) ctx.getBean("person2");
System.out.println(person2);
输出结果:
Person [name=Mike, address=Address [city=Beijing, street=Wudaokou], car=Car [brand=Aodi, price=100000.0]]
Person [name=Jack, address=Address [city=Beijing, street=Wudaokou], car=null]
请问一下大家,为什么使用depend-on设置依赖bean的时候,Car对象为空呢?depend-on和ref的有什么区别呢?
解决方案 »
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