bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/decorators/LightweightDecoratorDefinition.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.decorators;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.ISafeRunnable;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.jface.viewers.IBaseLabelProvider;
 import org.eclipse.jface.viewers.IDecoration;
 import org.eclipse.jface.viewers.ILightweightLabelDecorator;
 import org.eclipse.ui.internal.ActionExpression;
 import org.eclipse.ui.internal.IObjectContributor;
 import org.eclipse.ui.internal.LegacyResourceSupport;
 import org.eclipse.ui.internal.WorkbenchPlugin;

 /**
  * The DeclarativeDecoratorDefinition is a decorator definition that is defined
  * entirely from xml and will not require the activation of its defining
  * plug-in.
  */
 class LightweightDecoratorDefinition extends DecoratorDefinition implements
 		IObjectContributor {

 	private static final String ATT_LOCATION = "location"; //$NON-NLS-1$

 	static final String ATT_ICON = "icon"; //$NON-NLS-1$

 	// Constants for quadrants
 	/**
 	 * Position <code>TOP_LEFT</code>. Value <code>0</code>
 	 */
 	public static final int TOP_LEFT = 0;

 	/**
 	 * Position <code>TOP_RIGHT</code>. Value <code>1</code>
 	 */
 	public static final int TOP_RIGHT = 1;

 	/**
 	 * Position <code>BOTTOM_LEFT</code>. Value <code>2</code>
 	 */
 	public static final int BOTTOM_LEFT = 2;

 	/**
 	 * Position <code>BOTTOM_RIGHT</code>. Value <code>3</code>
 	 */
 	public static final int BOTTOM_RIGHT = 3;

 	/**
 	 * Position <code>UNDERLAY</code>. Value <code>4</code>
 	 */
 	public static final int UNDERLAY = 4;

 	private static final String UNDERLAY_STRING = "UNDERLAY"; //$NON-NLS-1$

 	private static final String ATT_QUADRANT = "quadrant"; //$NON-NLS-1$

 	// Constants for quadrants
 	private static final String TOP_LEFT_STRING = "TOP_LEFT"; //$NON-NLS-1$

 	private static final String TOP_RIGHT_STRING = "TOP_RIGHT"; //$NON-NLS-1$

 	private static final String BOTTOM_LEFT_STRING = "BOTTOM_LEFT"; //$NON-NLS-1$

 	/**
 	 * The DeclarativeDecorator is the internal decorator supplied by the
 	 * decorator definition.
 	 */
 	private ILightweightLabelDecorator decorator;

 	private int quadrant;

 	private boolean hasReadQuadrant;

 	private String[] objectClasses;

 	LightweightDecoratorDefinition(String identifier,
 			IConfigurationElement element) {
 		super(identifier, element);
 	}

 	/**
 	 * Gets the decorator and creates it if it does not exist yet. Throws a
 	 * CoreException if there is a problem creating the decorator. This method
 	 * should not be called unless a check for enabled to be true is done first.
 	 *
 	 * @return Returns a ILabelDecorator
 	 */
 	protected ILightweightLabelDecorator internalGetDecorator()
 			throws CoreException {
 		if (labelProviderCreationFailed) {
 			return null;
 		}

 		final CoreException[] exceptions = new CoreException[1];

 		if (decorator == null) {

 			if (isDeclarative()) {
 				decorator = new DeclarativeDecorator(definingElement,
 						getIconLocation());
 			} else {

 				Platform.run(new ISafeRunnable() {
 					public void run() {
 						try {
 							decorator = (ILightweightLabelDecorator) WorkbenchPlugin
 									.createExtension(definingElement,
 											DecoratorDefinition.ATT_CLASS);
 							decorator.addListener(WorkbenchPlugin.getDefault()
 									.getDecoratorManager());
 						} catch (CoreException exception) {
 							exceptions[0] = exception;
 						}
 					}

 					/*
 					 * (non-Javadoc) Method declared on ISafeRunnable.
 					 */
 					public void handleException(Throwable e) {
 						// Do nothing as Core will handle the logging
 					}
 				});
 			}
 		} else {
 			return decorator;
 		}

 		if (decorator == null) {
 			this.labelProviderCreationFailed = true;
 			setEnabled(false);
 		}

 		if (exceptions[0] != null) {
 			throw exceptions[0];
 		}

 		return decorator;
 	}

 	/**
 	 * Return whether or not this represents a declarative decorator.
 	 *
 	 * @return boolean <code>true</code> if this is declarative
 	 */
 	private boolean isDeclarative() {
 		return definingElement.getAttribute(DecoratorDefinition.ATT_CLASS) == null;
 	}

 	/**
 	 * Return the icon location.
 	 *
 	 * @return the icon location
 	 */
 	private String getIconLocation() {
 		return definingElement.getAttribute(ATT_ICON);
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.decorators.DecoratorDefinition#internalGetLabelProvider()
 	 */
 	protected IBaseLabelProvider internalGetLabelProvider()
 			throws CoreException {
 		return internalGetDecorator();
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.decorators.DecoratorDefinition#isFull()
 	 */
 	public boolean isFull() {
 		return false;
 	}

 	/**
 	 * Returns the quadrant.One of the following constants in
 	 * DecoratorRegistryReader: TOP_LEFT TOP_RIGHT BOTTOM_LEFT BOTTOM_RIGHT
 	 * UNDERLAY
 	 *
 	 * @return int
 	 */
 	public int getQuadrant() {
 		if (!hasReadQuadrant) {
 			hasReadQuadrant = true;
 			quadrant = getLocationConstant(definingElement
 					.getAttribute(ATT_LOCATION), definingElement);
 		}
 		return quadrant;
 	}

 	/**
 	 * Get the constant value based on the location supplied. Default to bottom
 	 * right.
 	 *
 	 * @since 3.1
 	 */
 	private int getLocationConstant(String locationDefinition,
 			IConfigurationElement element) {

 		// Backwards compatibility
 		if (locationDefinition == null) {
 			locationDefinition = element.getAttribute(ATT_QUADRANT);
 		}

 		if (TOP_RIGHT_STRING.equals(locationDefinition)) {
 			return TOP_RIGHT;
 		}
 		if (TOP_LEFT_STRING.equals(locationDefinition)) {
 			return TOP_LEFT;
 		}
 		if (BOTTOM_LEFT_STRING.equals(locationDefinition)) {
 			return BOTTOM_LEFT;
 		}
 		if (UNDERLAY_STRING.equals(locationDefinition)) {
 			return UNDERLAY;
 		}
 		return BOTTOM_RIGHT;

 	}

 	/**
 	 * Decorate the element using the decoration to store the result.
 	 * @param element
 	 * @param decoration
 	 */
 	public void decorate(Object element, IDecoration decoration) {
 		try {
 			// Internal decorator might be null so be prepared
 			ILightweightLabelDecorator currentDecorator = internalGetDecorator();
 			if(currentDecorator == null) {
 				return;
 			}

 			if (isAdaptable()) {
 				String[] classes = getObjectClasses();
 				for (int i = 0; i < classes.length; i++) {
 					String className = classes[i];
 					Object adapted = LegacyResourceSupport.getAdapter(element,
 							className);
 					if (adapted != null) {
 						currentDecorator.decorate(adapted, decoration);
 					}
 				}
 			}
 			else{
 				if (currentDecorator != null && element != null) {
 					currentDecorator.decorate(element, decoration);
 				}
 			}
 		} catch (CoreException exception) {
 			handleCoreException(exception);
 		}

 	}

 	/**
 	 * Returns the lightweight decorator, or <code>null</code> if not enabled.
 	 *
 	 * @return the lightweight decorator, or <code>null</code> if not enabled
 	 */
 	public ILightweightLabelDecorator getDecorator() {
 		return decorator;
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.decorators.DecoratorDefinition#refreshDecorator()
 	 */
 	protected void refreshDecorator() {
 		// Only do something if disabled so as to prevent
 		// gratutitous activation
 		if (!this.enabled && decorator != null) {
 			IBaseLabelProvider cached = decorator;
 			decorator = null;
 			disposeCachedDecorator(cached);
 		}
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.IObjectContributor#isApplicableTo(java.lang.Object)
 	 */
 	public boolean isApplicableTo(Object object) {
 		return isEnabledFor(object);
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.IObjectContributor#canAdapt()
 	 */
 	public boolean canAdapt() {
 		return isAdaptable();
 	}

 	/**
 	 * Get the object classes to which this decorator is registered.
 	 *
 	 * @return String [] the object classes to which this decorator is
 	 *         registered
 	 */
 	public String[] getObjectClasses() {
 		if (objectClasses == null) {
 			getEnablement();
 		}
 		return objectClasses;
 	}

 	/*
 	 * (non-Javadoc)
 	 *
 	 * @see org.eclipse.ui.internal.decorators.DecoratorDefinition#initializeEnablement()
 	 */
 	protected void initializeEnablement() {
 		super.initializeEnablement();
 		ActionExpression expression = getEnablement();
 		if (expression != null) {
 			objectClasses = expression.extractObjectClasses();
 		}

 		// If the class is null set it to Object
 		if (objectClasses == null) {
 			objectClasses = new String[] {Object.class.getName()};
 		}
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2006 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.internal.decorators;

	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IConfigurationElement;
	import org.eclipse.core.runtime.ISafeRunnable;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.jface.viewers.IBaseLabelProvider;
	import org.eclipse.jface.viewers.IDecoration;
	import org.eclipse.jface.viewers.ILightweightLabelDecorator;
	import org.eclipse.ui.internal.ActionExpression;
	import org.eclipse.ui.internal.IObjectContributor;
	import org.eclipse.ui.internal.LegacyResourceSupport;
	import org.eclipse.ui.internal.WorkbenchPlugin;

	/**
	* The DeclarativeDecoratorDefinition is a decorator definition that is defined
	* entirely from xml and will not require the activation of its defining
	* plug-in.
	*/
	class LightweightDecoratorDefinition extends DecoratorDefinition implements
	IObjectContributor {

	private static final String ATT_LOCATION = "location"; //$NON-NLS-1$

	static final String ATT_ICON = "icon"; //$NON-NLS-1$

	// Constants for quadrants
	/**
	* Position <code>TOP_LEFT</code>. Value <code>0</code>
	*/
	public static final int TOP_LEFT = 0;

	/**
	* Position <code>TOP_RIGHT</code>. Value <code>1</code>
	*/
	public static final int TOP_RIGHT = 1;

	/**
	* Position <code>BOTTOM_LEFT</code>. Value <code>2</code>
	*/
	public static final int BOTTOM_LEFT = 2;

	/**
	* Position <code>BOTTOM_RIGHT</code>. Value <code>3</code>
	*/
	public static final int BOTTOM_RIGHT = 3;

	/**
	* Position <code>UNDERLAY</code>. Value <code>4</code>
	*/
	public static final int UNDERLAY = 4;

	private static final String UNDERLAY_STRING = "UNDERLAY"; //$NON-NLS-1$

	private static final String ATT_QUADRANT = "quadrant"; //$NON-NLS-1$

	// Constants for quadrants
	private static final String TOP_LEFT_STRING = "TOP_LEFT"; //$NON-NLS-1$

	private static final String TOP_RIGHT_STRING = "TOP_RIGHT"; //$NON-NLS-1$

	private static final String BOTTOM_LEFT_STRING = "BOTTOM_LEFT"; //$NON-NLS-1$

	/**
	* The DeclarativeDecorator is the internal decorator supplied by the
	* decorator definition.
	*/
	private ILightweightLabelDecorator decorator;

	private int quadrant;

	private boolean hasReadQuadrant;

	private String[] objectClasses;

	LightweightDecoratorDefinition(String identifier,
	IConfigurationElement element) {
	super(identifier, element);
	}

	/**
	* Gets the decorator and creates it if it does not exist yet. Throws a
	* CoreException if there is a problem creating the decorator. This method
	* should not be called unless a check for enabled to be true is done first.
	*
	* @return Returns a ILabelDecorator
	*/
	protected ILightweightLabelDecorator internalGetDecorator()
	throws CoreException {
	if (labelProviderCreationFailed) {
	return null;
	}

	final CoreException[] exceptions = new CoreException[1];

	if (decorator == null) {

	if (isDeclarative()) {
	decorator = new DeclarativeDecorator(definingElement,
	getIconLocation());
	} else {

	Platform.run(new ISafeRunnable() {
	public void run() {
	try {
	decorator = (ILightweightLabelDecorator) WorkbenchPlugin
	.createExtension(definingElement,
	DecoratorDefinition.ATT_CLASS);
	decorator.addListener(WorkbenchPlugin.getDefault()
	.getDecoratorManager());
	} catch (CoreException exception) {
	exceptions[0] = exception;
	}
	}

	/*
	* (non-Javadoc) Method declared on ISafeRunnable.
	*/
	public void handleException(Throwable e) {
	// Do nothing as Core will handle the logging
	}
	});
	}
	} else {
	return decorator;
	}

	if (decorator == null) {
	this.labelProviderCreationFailed = true;
	setEnabled(false);
	}

	if (exceptions[0] != null) {
	throw exceptions[0];
	}

	return decorator;
	}

	/**
	* Return whether or not this represents a declarative decorator.
	*
	* @return boolean <code>true</code> if this is declarative
	*/
	private boolean isDeclarative() {
	return definingElement.getAttribute(DecoratorDefinition.ATT_CLASS) == null;
	}

	/**
	* Return the icon location.
	*
	* @return the icon location
	*/
	private String getIconLocation() {
	return definingElement.getAttribute(ATT_ICON);
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.decorators.DecoratorDefinition#internalGetLabelProvider()
	*/
	protected IBaseLabelProvider internalGetLabelProvider()
	throws CoreException {
	return internalGetDecorator();
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.decorators.DecoratorDefinition#isFull()
	*/
	public boolean isFull() {
	return false;
	}

	/**
	* Returns the quadrant.One of the following constants in
	* DecoratorRegistryReader: TOP_LEFT TOP_RIGHT BOTTOM_LEFT BOTTOM_RIGHT
	* UNDERLAY
	*
	* @return int
	*/
	public int getQuadrant() {
	if (!hasReadQuadrant) {
	hasReadQuadrant = true;
	quadrant = getLocationConstant(definingElement
	.getAttribute(ATT_LOCATION), definingElement);
	}
	return quadrant;
	}

	/**
	* Get the constant value based on the location supplied. Default to bottom
	* right.
	*
	* @since 3.1
	*/
	private int getLocationConstant(String locationDefinition,
	IConfigurationElement element) {

	// Backwards compatibility
	if (locationDefinition == null) {
	locationDefinition = element.getAttribute(ATT_QUADRANT);
	}

	if (TOP_RIGHT_STRING.equals(locationDefinition)) {
	return TOP_RIGHT;
	}
	if (TOP_LEFT_STRING.equals(locationDefinition)) {
	return TOP_LEFT;
	}
	if (BOTTOM_LEFT_STRING.equals(locationDefinition)) {
	return BOTTOM_LEFT;
	}
	if (UNDERLAY_STRING.equals(locationDefinition)) {
	return UNDERLAY;
	}
	return BOTTOM_RIGHT;

	}

	/**
	* Decorate the element using the decoration to store the result.
	* @param element
	* @param decoration
	*/
	public void decorate(Object element, IDecoration decoration) {
	try {
	// Internal decorator might be null so be prepared
	ILightweightLabelDecorator currentDecorator = internalGetDecorator();
	if(currentDecorator == null) {
	return;
	}

	if (isAdaptable()) {
	String[] classes = getObjectClasses();
	for (int i = 0; i < classes.length; i++) {
	String className = classes[i];
	Object adapted = LegacyResourceSupport.getAdapter(element,
	className);
	if (adapted != null) {
	currentDecorator.decorate(adapted, decoration);
	}
	}
	}
	else{
	if (currentDecorator != null && element != null) {
	currentDecorator.decorate(element, decoration);
	}
	}
	} catch (CoreException exception) {
	handleCoreException(exception);
	}

	}

	/**
	* Returns the lightweight decorator, or <code>null</code> if not enabled.
	*
	* @return the lightweight decorator, or <code>null</code> if not enabled
	*/
	public ILightweightLabelDecorator getDecorator() {
	return decorator;
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.decorators.DecoratorDefinition#refreshDecorator()
	*/
	protected void refreshDecorator() {
	// Only do something if disabled so as to prevent
	// gratutitous activation
	if (!this.enabled && decorator != null) {
	IBaseLabelProvider cached = decorator;
	decorator = null;
	disposeCachedDecorator(cached);
	}
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.IObjectContributor#isApplicableTo(java.lang.Object)
	*/
	public boolean isApplicableTo(Object object) {
	return isEnabledFor(object);
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.IObjectContributor#canAdapt()
	*/
	public boolean canAdapt() {
	return isAdaptable();
	}

	/**
	* Get the object classes to which this decorator is registered.
	*
	* @return String [] the object classes to which this decorator is
	* registered
	*/
	public String[] getObjectClasses() {
	if (objectClasses == null) {
	getEnablement();
	}
	return objectClasses;
	}

	/*
	* (non-Javadoc)
	*
	* @see org.eclipse.ui.internal.decorators.DecoratorDefinition#initializeEnablement()
	*/
	protected void initializeEnablement() {
	super.initializeEnablement();
	ActionExpression expression = getEnablement();
	if (expression != null) {
	objectClasses = expression.extractObjectClasses();
	}

	// If the class is null set it to Object
	if (objectClasses == null) {
	objectClasses = new String[] {Object.class.getName()};
	}
	}

	}