Back to index...

	/*
	* Copyright (c) 1998, 2006, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* (C) Copyright Taligent, Inc. 1996 - 1997, All Rights Reserved
	* (C) Copyright IBM Corp. 1996 - 1998, All Rights Reserved
	*
	* The original version of this source code and documentation is
	* copyrighted and owned by Taligent, Inc., a wholly-owned subsidiary
	* of IBM. These materials are provided under terms of a License
	* Agreement between Taligent and Sun. This technology is protected
	* by multiple US and International patents.
	*
	* This notice and attribution to Taligent may not be removed.
	* Taligent is a registered trademark of Taligent, Inc.
	*
	*/

	package java.awt.font;

	import java.awt.Graphics2D;
	import java.awt.Font;
	import java.awt.Shape;
	import java.awt.geom.AffineTransform;
	import java.awt.geom.Rectangle2D;

	/**
	* This class is used with the CHAR_REPLACEMENT attribute.
	* <p>
	* The <code>GraphicAttribute</code> class represents a graphic embedded
	* in text. Clients subclass this class to implement their own char
	* replacement graphics. Clients wishing to embed shapes and images in
	* text need not subclass this class. Instead, clients can use the
	* {@link ShapeGraphicAttribute} and {@link ImageGraphicAttribute}
	* classes.
	* <p>
	* Subclasses must ensure that their objects are immutable once they
	* are constructed. Mutating a <code>GraphicAttribute</code> that
	* is used in a {@link TextLayout} results in undefined behavior from the
	* <code>TextLayout</code>.
	*/
	public abstract class GraphicAttribute {

	private int fAlignment;

	/**
	* Aligns top of graphic to top of line.
	*/
	public static final int TOP_ALIGNMENT = -1;

	/**
	* Aligns bottom of graphic to bottom of line.
	*/
	public static final int BOTTOM_ALIGNMENT = -2;

	/**
	* Aligns origin of graphic to roman baseline of line.
	*/
	public static final int ROMAN_BASELINE = Font.ROMAN_BASELINE;

	/**
	* Aligns origin of graphic to center baseline of line.
	*/
	public static final int CENTER_BASELINE = Font.CENTER_BASELINE;

	/**
	* Aligns origin of graphic to hanging baseline of line.
	*/
	public static final int HANGING_BASELINE = Font.HANGING_BASELINE;

	/**
	* Constructs a <code>GraphicAttribute</code>.
	* Subclasses use this to define the alignment of the graphic.
	* @param alignment an int representing one of the
	* <code>GraphicAttribute</code> alignment fields
	* @throws IllegalArgumentException if alignment is not one of the
	* five defined values.
	*/
	protected GraphicAttribute(int alignment) {
	if (alignment < BOTTOM_ALIGNMENT \|\| alignment > HANGING_BASELINE) {
	throw new IllegalArgumentException("bad alignment");
	}
	fAlignment = alignment;
	}

	/**
	* Returns the ascent of this <code>GraphicAttribute</code>. A
	* graphic can be rendered above its ascent.
	* @return the ascent of this <code>GraphicAttribute</code>.
	* @see #getBounds()
	*/
	public abstract float getAscent();


	/**
	* Returns the descent of this <code>GraphicAttribute</code>. A
	* graphic can be rendered below its descent.
	* @return the descent of this <code>GraphicAttribute</code>.
	* @see #getBounds()
	*/
	public abstract float getDescent();

	/**
	* Returns the advance of this <code>GraphicAttribute</code>. The
	* <code>GraphicAttribute</code> object's advance is the distance
	* from the point at which the graphic is rendered and the point where
	* the next character or graphic is rendered. A graphic can be
	* rendered beyond its advance
	* @return the advance of this <code>GraphicAttribute</code>.
	* @see #getBounds()
	*/
	public abstract float getAdvance();

	/**
	* Returns a {@link Rectangle2D} that encloses all of the
	* bits drawn by this <code>GraphicAttribute</code> relative to the
	* rendering position.
	* A graphic may be rendered beyond its origin, ascent, descent,
	* or advance; but if it is, this method's implementation must
	* indicate where the graphic is rendered.
	* Default bounds is the rectangle (0, -ascent, advance, ascent+descent).
	* @return a <code>Rectangle2D</code> that encloses all of the bits
	* rendered by this <code>GraphicAttribute</code>.
	*/
	public Rectangle2D getBounds() {
	float ascent = getAscent();
	return new Rectangle2D.Float(0, -ascent,
	getAdvance(), ascent+getDescent());
	}

	/**
	* Return a {@link java.awt.Shape} that represents the region that
	* this <code>GraphicAttribute</code> renders. This is used when a
	* {@link TextLayout} is requested to return the outline of the text.
	* The (untransformed) shape must not extend outside the rectangular
	* bounds returned by <code>getBounds</code>.
	* The default implementation returns the rectangle returned by
	* {@link #getBounds}, transformed by the provided {@link AffineTransform}
	* if present.
	* @param tx an optional {@link AffineTransform} to apply to the
	* outline of this <code>GraphicAttribute</code>. This can be null.
	* @return a <code>Shape</code> representing this graphic attribute,
	* suitable for stroking or filling.
	* @since 1.6
	*/
	public Shape getOutline(AffineTransform tx) {
	Shape b = getBounds();
	if (tx != null) {
	b = tx.createTransformedShape(b);
	}
	return b;
	}

	/**
	* Renders this <code>GraphicAttribute</code> at the specified
	* location.
	* @param graphics the {@link Graphics2D} into which to render the
	* graphic
	* @param x the user-space X coordinate where the graphic is rendered
	* @param y the user-space Y coordinate where the graphic is rendered
	*/
	public abstract void draw(Graphics2D graphics, float x, float y);

	/**
	* Returns the alignment of this <code>GraphicAttribute</code>.
	* Alignment can be to a particular baseline, or to the absolute top
	* or bottom of a line.
	* @return the alignment of this <code>GraphicAttribute</code>.
	*/
	public final int getAlignment() {

	return fAlignment;
	}

	/**
	* Returns the justification information for this
	* <code>GraphicAttribute</code>. Subclasses
	* can override this method to provide different justification
	* information.
	* @return a {@link GlyphJustificationInfo} object that contains the
	* justification information for this <code>GraphicAttribute</code>.
	*/
	public GlyphJustificationInfo getJustificationInfo() {

	// should we cache this?
	float advance = getAdvance();

	return new GlyphJustificationInfo(
	advance, // weight
	false, // growAbsorb
	2, // growPriority
	advance/3, // growLeftLimit
	advance/3, // growRightLimit
	false, // shrinkAbsorb
	1, // shrinkPriority
	0, // shrinkLeftLimit
	0); // shrinkRightLimit
	}
	}

Back to index...