org.scijava.plugin.PluginService Maven / Gradle / Ivy
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/*
* #%L
* SciJava Common shared library for SciJava software.
* %%
* Copyright (C) 2009 - 2017 Board of Regents of the University of
* 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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* modification, are permitted provided that the following conditions are met:
*
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* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
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*
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package org.scijava.plugin;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
import org.scijava.Priority;
import org.scijava.service.SciJavaService;
/**
* Interface for service that keeps track of available plugins.
*
* The plugin service keeps a master index of all plugins known to the system.
* At heart, a plugin is a piece of functionality that extends a program's
* capabilities. Plugins take many forms; see {@link SciJavaPlugin} for details.
*
*
* The default plugin service discovers available plugins on the classpath.
*
*
* @author Curtis Rueden
* @see SciJavaPlugin
*/
public interface PluginService extends SciJavaService {
/** Gets the index of available plugins. */
PluginIndex getIndex();
/**
* Rediscovers all plugins available on the classpath. Note that this will
* clear any individual plugins added programmatically.
*/
void reloadPlugins();
/** Manually registers a plugin with the plugin service. */
void addPlugin(PluginInfo plugin);
/** Manually registers plugins with the plugin service. */
> void addPlugins(Collection plugins);
/** Manually unregisters a plugin with the plugin service. */
void removePlugin(PluginInfo plugin);
/** Manually unregisters plugins with the plugin service. */
> void removePlugins(Collection plugins);
/** Gets the list of known plugins. */
List> getPlugins();
/**
* Gets the first available plugin of the given class, or null if none.
*
* @param The class of the plugin to look up.
*/
PluginInfo
getPlugin(Class pluginClass);
/**
* Gets the first available plugin of the given class, or null if none.
*
* @param The type of the plugin to look up; e.g.,
* {@code Service.class}.
* @param The class of the plugin to look up.
*/
PluginInfo
getPlugin(Class pluginClass, Class type);
/**
* Gets the first available plugin of the given class name, or null if none.
*/
PluginInfo getPlugin(String className);
/**
* Gets the list of plugins of the given type (e.g.,
* {@link org.scijava.service.Service}).
*
* @param The type of plugins to look up; e.g.,
* {@code Service.class}.
*/
List>
getPluginsOfType(Class type);
/**
* Gets the list of plugins of the given class.
*
* Most classes will have only a single match, but some special classes (such
* as ImageJ's {@code LegacyCommand}) may match many entries.
*
*
* Note that this method will result in {@link PluginInfo}s with matching
* class names to load their plugin {@link Class}es so that they can
* be compared with the given one.
*
*
* NB: Classes are matched by strict equality, not assignability; subtypes of
* the specified class will not match. For this behavior, use
* {@link #getPluginsOfType(Class)} on a common parent interface.
*
*
* @param The class of plugins to look up.
* @param pluginClass The class for which to obtain the list of matching
* plugins.
*/
List>
getPluginsOfClass(Class pluginClass);
/**
* Gets the list of plugins of the given class.
*
* Most classes will have only a single match, but some special classes (such
* as ImageJ's {@code LegacyCommand}) may match many entries.
*
*
* Note that this method will result in {@link PluginInfo}s with matching
* class names and types to load their plugin {@link Class}es so that
* they can be compared with the given one.
*
*
* NB: Classes are matched by strict equality, not assignability; subtypes of
* the specified class will not match. For this behavior, use
* {@link #getPluginsOfType(Class)} on a common parent interface.
*
*
* @param The type of plugins to look up; e.g.,
* {@code Service.class}.
* @param The class of plugins to look up.
* @param pluginClass The class for which to obtain the list of matching
* plugins.
* @param type The type of plugins to which the search should be
* limited.
*/
List>
getPluginsOfClass(Class pluginClass, Class type);
/**
* Gets the list of plugins with the given class name.
*
* Most classes will have only a single match, but some special classes (such
* as ImageJ's {@code LegacyCommand}) may match many entries.
*
*
* NB: Classes are matched by strict equality, not assignability; subtypes of
* the specified class will not match. For this behavior, use
* {@link #getPluginsOfType(Class)} on a common parent interface.
*
*
* @param className The class name for which to obtain the list of matching
* plugins.
*/
List> getPluginsOfClass(String className);
/**
* Gets the list of plugins with the given class name.
*
* Most classes will have only a single match, but some special classes (such
* as ImageJ's {@code LegacyCommand}) may match many entries.
*
*
* NB: Classes are matched by strict equality, not assignability; subtypes of
* the specified class will not match. For this behavior, use
* {@link #getPluginsOfType(Class)} on a common parent interface.
*
*
* @param The type of plugins to look up; e.g.,
* {@code Service.class}.
* @param className The class name for which to obtain the list of matching
* plugins.
* @param type The type of plugins to which the search should be
* limited.
*/
List>
getPluginsOfClass(final String className, final Class type);
/**
* Creates one instance each of the available plugins of the given type.
*
* Note that in the case of commands, this method does not do any
* preprocessing on the command instances, so parameters will not be
* auto-populated, initializers will not be executed, etc.
*
*
* @param The type of plugins to instantiate; e.g.,
* {@code Service.class}.
*/
List createInstancesOfType(Class type);
/**
* Creates an instance of each of the plugins on the given list.
*
* If the plugin implements the {@link org.scijava.Contextual} interface, the
* appropriate context is injected. Similarly, if the plugin implements the
* {@link org.scijava.Prioritized} interface, the appropriate priority is
* injected.
*
*
* Note that in the case of commands, this method does not do any
* preprocessing on the command instances, so parameters will not be
* auto-populated, initializers will not be executed, etc.
*
*
* @param The type of plugins to instantiate; e.g.,
* {@code Service.class}.
*/
List
createInstances(List> infos);
/**
* Creates an instance of the given plugin.
*
* If the plugin implements the {@link org.scijava.Contextual} interface, the
* appropriate context is injected. Similarly, if the plugin implements the
* {@link org.scijava.Prioritized} interface, the appropriate priority is
* injected.
*
*
* Note that in the case of commands, this method does not do any
* preprocessing on the command instances, so parameters will not be
* auto-populated, initializers will not be executed, etc.
*
*
* @param The type of plugin to instantiate; e.g.,
* {@code Service.class}.
*/
PT createInstance(PluginInfo info);
/**
* Sorts the given list of plugin instances by priority.
*
* @param instances List of plugin instances to sort.
* @param type The type of plugin these instances represent.
*/
default void sort(final List instances,
final Class type)
{
// Create a mapping from plugin classes to priorities.
final List> plugins = getPluginsOfType(type);
final Map, PluginInfo> infos = plugins.stream().collect(//
Collectors.toMap(PluginInfo::getPluginClass, Function.identity()));
// Compare plugin instances by priority via the mapping.
final Comparator comparator = (o1, o2) -> Priority.compare(//
infos.get(o1.getClass()), infos.get(o2.getClass()));
Collections.sort(instances, comparator);
}
}