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Showing posts from June, 2013

Creating Spring Bean dynamically in the Runtime

In my training someone asked me whether it is possible to create an object (a Spring Bean) dynamically so you can choose which implementation you want to have in the runtime. So at the compile time you don't know what object actually should be created yet. The application should decide what object to be created based on a property file.

1. We create an annotation so we can mark the method which should be able to create the object dynamically:

...
package your.package;
...
@Retention(RetentionPolicy.RUNTIME)
public @interface InjectDynamicObject {
}
...
2. Use the new created annotation in your method which should be able to create the object dynamically:
... @Named("customerBo") public class CustomerBoImpl implements CustomerBo { ...     @Override @InjectDynamicObject public Customer getDynamicCustomer() {         return this.dynamicCustomer; } ...
3. Write an aspect with Pointcut and Advise which change the object returned by the method in the step 2:
... @Named @Aspect public class Dyn…