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SciJava Common is a shared library for SciJava software. It provides a plugin framework, with an extensible mechanism for service discovery, backed by its own annotation processor, so that plugins can be loaded dynamically. It is used by downstream projects in the SciJava ecosystem, such as ImageJ and SCIFIO.
/*
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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
* Konstanz, and KNIME GmbH.
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package org.scijava.plugin;
import java.util.List;
/**
* A service for managing {@link HandlerPlugin}s of a particular type.
*
* For any given data object, the service is capable of determining the most
* appropriate handler by sequentially querying each handler plugin on its list
* (via {@link HandlerPlugin#supports}).
*
*
* @author Curtis Rueden
* @param Base data type handled by the handlers.
* @param Plugin type of the handlers.
* @see HandlerPlugin
*/
public interface HandlerService> extends
SingletonService, TypedService
{
/**
* Gets the most appropriate handler for the given data object, or null if no
* handler supports it.
*/
default PT getHandler(final DT data) {
for (final PT handler : getInstances()) {
if (handler.supports(data)) return handler;
}
return null;
}
// -- SingletonService methods --
/**
* Gets the list of handlers. There will be one singleton instance for each
* available handler plugin.
*/
@Override
List getInstances();
// -- Typed methods --
/** Gets whether the given data object is supported. */
@Override
default boolean supports(final DT data) {
return getHandler(data) != null;
}
}