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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
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 *
 * The contents of this file are subject to the terms of either the GNU
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 * Development and Distribution License("CDDL") (collectively, the
 * "License"). You may not use this file except in compliance with the
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 * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
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package org.netbeans.spi.debugger;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Constructor;
import java.util.Set;
import org.openide.util.RequestProcessor;

/**
 * Represents implementation of one or more actions.
 *
 * @author   Jan Jancura
 */
public abstract class ActionsProvider implements ContextAwareService<ActionsProvider> {

    public ActionsProvider() {}

    public ActionsProvider(ContextProvider context) {
        this();
    }

    /**
     * Returns set of actions supported by this ActionsProvider.
     *
     * @return set of actions supported by this ActionsProvider
     */
    public abstract Set getActions ();

    /**
     * Called when the action is called (action button is pressed).
     *
     * @param action an action which has been called
     */
    public abstract void doAction (Object action);
    
    /**
     * Should return a state of given action.
     *
     * @param action action
     */
    public abstract boolean isEnabled (Object action);
    
    /**
     * Adds property change listener.
     *
     * @param l new listener.
     */
    public abstract void addActionsProviderListener (ActionsProviderListener l);
    

    /**
     * Removes property change listener.
     *
     * @param l removed listener.
     */
    public abstract void removeActionsProviderListener (ActionsProviderListener l);
    
    /**
     * Post the action and let it process asynchronously.
     * The default implementation just delegates to {@link #doAction}
     * in a separate thread and returns immediately.
     *
     * @param action The action to post
     * @param actionPerformedNotifier run this notifier after the action is
     *        done.
     * @since 1.5
     */
    public void postAction (final Object action,
                            final Runnable actionPerformedNotifier) {
        RequestProcessor.getDefault().post(new Runnable() {
            public void run() {
                try {
                    doAction(action);
                } finally {
                    actionPerformedNotifier.run();
                }
            }
        });
    }

    public ActionsProvider forContext(ContextProvider context) {
        Class clazz = getClass();
        try {
            Constructor<ActionsProvider> c = clazz.getConstructor(ContextProvider.class);
            try {
                return c.newInstance(context);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        } catch (NoSuchMethodException ex) {
            try {
                return getClass().newInstance();
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
        
    }

    @Retention(RetentionPolicy.SOURCE)
    @Target({ElementType.TYPE})
    public @interface Registration {
        /**
         * An optional path to register this implementation in.
         */
        String path() default "";

    }
    
}