IAnnotationAccessExtension.java

/*******************************************************************************
 * Copyright (c) 2000, 2007 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.jface.text.source;

import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Canvas;

/**
 * Extension interface for {@link org.eclipse.jface.text.source.IAnnotationAccess}.<p>
 * This interface replaces the methods of <code>IAnnotationAccess</code>.<p>
 * This interface provides
 * <ul>
 * <li> a label for the annotation type of a given annotation</li>
 * <li> the paint layer of a given annotation</li>
 * <li> means to paint a given annotation</li>
 * <li> information about the type hierarchy of the annotation type of a given annotation</li>
 * <ul>.
 *
 * @see org.eclipse.jface.text.source.IAnnotationAccess
 * @since 3.0
 */
public interface IAnnotationAccessExtension {

	/**
	 * The default annotation layer.
	 */
	static final int DEFAULT_LAYER= IAnnotationPresentation.DEFAULT_LAYER;

	/**
	 * Returns the label for the given annotation's type.
	 *
	 * @param annotation the annotation
	 * @return the label the given annotation's type or <code>null</code> if no such label exists
	 */
	String getTypeLabel(Annotation annotation);

	/**
	 * Returns the layer for given annotation. Annotations are considered
	 * being located at layers and are considered being painted starting with
	 * layer 0 upwards. Thus an annotation at layer 5 will be drawn on top of
	 * all co-located annotations at the layers 4 - 0.
	 *
	 * @param annotation the annotation
	 * @return the layer of the given annotation
	 */
	int getLayer(Annotation annotation);

	/**
	 * Draws a graphical representation of the given annotation within the given bounds.
	 * <p>
	 * <em>Note that this method is not used when drawing annotations on the editor's
	 * text widget. This is handled trough a {@link org.eclipse.jface.text.source.AnnotationPainter.IDrawingStrategy}.</em>
	 * </p>
	 * @param annotation the given annotation
	 * @param gc the drawing GC
	 * @param canvas the canvas to draw on
	 * @param bounds the bounds inside the canvas to draw on
	 */
	void paint(Annotation annotation, GC gc, Canvas canvas, Rectangle bounds);

	/**
	 * Returns <code>true</code> if painting <code>annotation</code> will produce something
	 * meaningful, <code>false</code> if not. E.g. if no image is available.
	 * <p>
	 * <em>Note that this method is not used when drawing annotations on the editor's
	 * text widget. This is handled trough a {@link org.eclipse.jface.text.source.AnnotationPainter.IDrawingStrategy}.</em>
	 * </p>
	 * @param annotation the annotation to check whether it can be painted
	 * @return <code>true</code> if painting <code>annotation</code> will succeed
	 */
	boolean isPaintable(Annotation annotation);

	/**
	 * Returns <code>true</code> if the given annotation is of the given type
	 * or <code>false</code> otherwise.
	 *
	 * @param annotationType the annotation type
	 * @param potentialSupertype the potential super annotation type
	 * @return <code>true</code> if annotation type is a sub-type of the potential annotation super type
	 */
	boolean isSubtype(Object annotationType, Object potentialSupertype);

	/**
	 * Returns the list of super types for the given annotation type. This does not include the type
	 * itself. The index in the array of super types indicates the length of the path in the hierarchy
	 * graph to the given annotation type.
	 *
	 * @param annotationType the annotation type to check
	 * @return the super types for the given annotation type
	 */
	Object[] getSupertypes(Object annotationType);
}