org.scijava.service.Service Maven / Gradle / Ivy
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* SciJava Common shared library for SciJava software.
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* Wisconsin-Madison, Broad Institute of MIT and Harvard, Max Planck
* Institute of Molecular Cell Biology and Genetics, University of
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package org.scijava.service;
import org.scijava.Disposable;
import org.scijava.Initializable;
import org.scijava.event.EventService;
import org.scijava.plugin.Plugin;
import org.scijava.plugin.RichPlugin;
/**
* A SciJava service, for a particular area of functionality.
*
* Services discoverable at runtime must implement this interface and be
* annotated with @{@link Plugin} with attribute {@link Plugin#type()} =
* {@link Service}.class. While it possible to create a service merely by
* implementing this interface, it is encouraged to instead extend
* {@link AbstractService}, for convenience.
*
*
* @author Curtis Rueden
* @see Plugin
*/
public interface Service extends RichPlugin, Initializable, Disposable {
/**
* Registers the service's event handler methods.
*
* NB: This method is not intended to be called directly. It is called by
* the service framework itself (specifically by the {@link ServiceHelper})
* when initializing the service. It should not be called a second time.
*
*/
default void registerEventHandlers() {
// TODO: Consider removing this method in scijava-common 3.0.0.
// Instead, the ServiceHelper could just invoke the lines below directly,
// and there would be one less boilerplate Service method to implement.
final EventService eventService = context().getService(EventService.class);
if (eventService != null) eventService.subscribe(this);
}
// -- Initializable methods --
/**
* Performs any needed initialization when the service is first loaded.
*
* NB: This method is not intended to be called directly. It is called by
* the service framework itself (specifically by the {@link ServiceHelper})
* when initializing the service. It should not be called a second time.
*
*/
@Override
default void initialize() {
// NB: Do nothing by default.
}
}