Cannot inject Spring-bean in class

Question

I have following class:

@Component("persistenceJPAConfig")
public class JPAPersistenceConfig {...}

Using Spring I am able to "inject" the class by adding a method with @Autowired-annotation in my target Class where I want to use JPAPersistenceConfig - Class. I works fine, the class itself is fine.

The Problem is that I have to create a Class at runtime (writing source code and compile it) that has to use the bean as well.

I added the autowired-methods too, but it keeps to be null.

@org.springframework.stereotype.Component("Customers")
public class Customers  {
    public Customers() {
    }
    private org.product.server.database.JPAPersistenceConfig persistenceJPAConfig; 

    @org.springframework.beans.factory.annotation.Autowired 
    public void setPersistenceJPAConfig(org.product.server.database.JPAPersistenceConfig persistenceJPAConfig) {
        this.persistenceJPAConfig = persistenceJPAConfig;
    }  
    public void someMethod() {
        this.persistenceJPAConfig.getClassByName(...)
        // Throws nullpointer
    }
}

Do I have to mark the generated file with @Component too so that it becomes a "managed bean" in Spring? And how is it registered in Spring at runtime?

desperately yours :-)

can you post your Spring Bean Definition File? – ElderMael Sep 28 '12 at 15:03 — ElderMael, Sep 28 '12 at 15:03
how do you create new class in runtime? – vacuum Sep 28 '12 at 15:25 — vacuum, Sep 28 '12 at 15:25

score 0 · Accepted Answer · answered Sep 28 '12 at 15:32

0

You can regiter bean in runtime:

DefaultListableBeanFactory beanFactory = (DefaultListableBeanFactory) applicationContext.getBeanFactory();
beanFactory.registerBeanDefinition("myClass", BeanDefinitionBuilder.rootBeanDefinition(MyClass.class.getName()).getBeanDefinition());

And if your class have autowired properties, they also will be injected.

answered Sep 28 '12 at 15:32

vacuum

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Perfect :-) Thank you all, vaccum and AdolfoV – Randbedingung Oct 02 '12 at 07:15

score 0 · Answer 2 · edited May 23 '17 at 12:04

0

Besides what @vacuum said you can annotate the generated class with @Component and scan it at runtime to generate the bean with its dependencies using ClassPathScanningCandidateComponentProvider, look here

edited May 23 '17 at 12:04

Community

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answered Sep 28 '12 at 15:37

Adolfo

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Cannot inject Spring-bean in class

2 Answers2