org.jvnet.hk2.component.Factory Maven / Gradle / Ivy
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package org.jvnet.hk2.component;
import org.jvnet.hk2.annotations.Service;
/**
* Hook to create/obtain an instance of a component from
* somewhere, instead of letting the auto-depends create it
* via the constructor.
*
*
* {@link Factory} is by itself a component, so the factory
* implementation could have everything it needs injected.
*
* @author Kohsuke Kawaguchi
* @see Service
*/
public interface Factory {
/**
* The system calls this method to obtain a reference
* to the component.
*
* @return
* null is a valid return value. This is useful
* when a factory primarily does a look-up and it fails
* to find the specified component, yet you don't want that
* by itself to be an error. If the injection wants
* a non-null value (i.e., @Inject(optional=false)).
* @throws ComponentException
* If the factory failed to get/create an instance
* and would like to propagate the error to the caller.
*/
Object getObject() throws ComponentException;
}