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@Autowired by constructor looks for beans by type. How to inject a bean by name to a constructor using autowired annotation? I have 2 beans of same type but I need to inject it to constructor of another same class based on the bean name. How do I do it?
XML:
<bean id="A" class="com.Check"/> <bean id="B" class="com.Check"/> Java:
Class C { private Check check; @Autowired public C(Check check){ this.check = check } } When I do this I get an exception telling me that I have 2 beans of same type check but it requires there to be just one bean of that type. How can I inject the bean with id="B" into this class C through constructor injection?
In my applicationContext.xml I have mentioned autowire="byType". I need to autowire byName only in this particular class rest all it needs to be autowired by Type only
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if Spring encounters multiple beans with same type it checks field name. if it finds a bean with the name of the target field, it injects that bean into the field.
You can apply @Autowired to constructors as well. A constructor @Autowired annotation indicates that the constructor should be autowired when creating the bean, even if no <constructor-arg> elements are used while configuring the bean in XML file.
Autowiring by Name. Spring uses the bean's name as a default qualifier value. It will inspect the container and look for a bean with the exact name as the property to autowire it.
Enabling @Autowired annotation By declaring beans, you provide metadata to the Spring Container to return the required dependency object at runtime. This is called Spring Bean Autowiring. In java based configuration, all the bean methods are defined in the class with @configuration annotation.
You should use @Qualifier annotation with your target bean id for constructor parameter.
<bean id="A" class="com.Check"/> <bean id="B" class="com.Check"/> Class C { private Check check; @Autowired public C(@Qualifier("A") Check check){ //<-- here you should provide your target bean id this.check = check } } If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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