diff options
author | Tom Tromey <tromey@gcc.gnu.org> | 2005-07-16 00:30:23 +0000 |
---|---|---|
committer | Tom Tromey <tromey@gcc.gnu.org> | 2005-07-16 00:30:23 +0000 |
commit | f911ba985aa7fe0096c386c5be385ac5825ea527 (patch) | |
tree | a0b991cf5866ae1d616639b906ac001811d74508 /libjava/classpath/java/awt/FontMetrics.java | |
parent | 6f4434b39b261de5317dc81ddfdd94d2e1d62b11 (diff) | |
download | gcc-f911ba985aa7fe0096c386c5be385ac5825ea527.zip gcc-f911ba985aa7fe0096c386c5be385ac5825ea527.tar.gz gcc-f911ba985aa7fe0096c386c5be385ac5825ea527.tar.bz2 |
Initial revision
From-SVN: r102074
Diffstat (limited to 'libjava/classpath/java/awt/FontMetrics.java')
-rw-r--r-- | libjava/classpath/java/awt/FontMetrics.java | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/libjava/classpath/java/awt/FontMetrics.java b/libjava/classpath/java/awt/FontMetrics.java new file mode 100644 index 0000000..e702a62 --- /dev/null +++ b/libjava/classpath/java/awt/FontMetrics.java @@ -0,0 +1,425 @@ +/* FontMetrics.java -- Information about about a fonts display characteristics + Copyright (C) 1999, 2002, 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.awt; + +import java.awt.font.FontRenderContext; +import java.awt.font.LineMetrics; +import java.awt.geom.Rectangle2D; +import java.text.CharacterIterator; + +// FIXME: I leave many methods basically unimplemented. This +// should be reviewed. + +/** + * This class returns information about the display characteristics of + * a font. It is abstract, and concrete subclasses should implement at + * least the following methods: + * + * <ul> + * <li>getAscent()</li> + * <li>getDescent()</li> + * <li>getLeading()</li> + * <li>getMaxAdvance()</li> + * <li>charWidth(char)</li> + * <li>charsWidth(char[], int, int)</li> + * </ul> + * + * @author Aaron M. Renn (arenn@urbanophile.com) + */ +public abstract class FontMetrics implements java.io.Serializable +{ + // Serialization constant. + private static final long serialVersionUID = 1681126225205050147L; + + /** + * This is the font for which metrics will be returned. + */ + protected Font font; + + /** + * Initializes a new instance of <code>FontMetrics</code> for the + * specified font. + * + * @param font The font to return metric information for. + */ + protected FontMetrics(Font font) + { + this.font = font; + } + + /** + * Returns the font that this object is creating metric information fo. + * + * @return The font for this object. + */ + public Font getFont() + { + return font; + } + + /** + * Returns the leading, or spacing between lines, for this font. + * + * @return The font leading. + */ + public int getLeading() + { + return 0; + } + + /** + * Returns the ascent of the font, which is the distance from the base + * to the top of the majority of characters in the set. Some characters + * can exceed this value however. + * + * @return The font ascent. + */ + public int getAscent() + { + return 1; + } + + /** + * Returns the descent of the font, which is the distance from the base + * to the bottom of the majority of characters in the set. Some characters + * can exceed this value however. + * + * @return The font descent. + */ + public int getDescent() + { + return 1; + } + + /** + * Returns the height of a line in this font. This will be the sum + * of the leading, the ascent, and the descent. + * + * @return The height of the font. + */ + public int getHeight() + { + return getAscent() + getDescent() + getLeading(); + } + + /** + * Returns the maximum ascent value. This is the maximum distance any + * character in the font rised above the baseline. + * + * @return The maximum ascent for this font. + */ + public int getMaxAscent() + { + return getAscent(); + } + + /** + * Returns the maximum descent value. This is the maximum distance any + * character in the font extends below the baseline. + * + * @return The maximum descent for this font. + */ + public int getMaxDescent() + { + return getMaxDecent(); + } + + /** + * Returns the maximum descent value. This is the maximum distance any + * character in the font extends below the baseline. + * + * @return The maximum descent for this font. + * + * @deprecated This method is deprecated in favor of + * <code>getMaxDescent()</code>. + */ + public int getMaxDecent() + { + return getDescent(); + } + + /** + * Returns the width of the widest character in the font. + * + * @return The width of the widest character in the font. + */ + public int getMaxAdvance() + { + return -1; + } + + /** + * Returns the width of the specified character. + * + * @param ch The character to return the width of. + * + * @return The width of the specified character. + */ + public int charWidth(int ch) + { + return charWidth((char) ch); + } + + /** + * Returns the width of the specified character. + * + * @param ch The character to return the width of. + * + * @return The width of the specified character. + */ + public int charWidth(char ch) + { + return 1; + } + + /** + * Returns the total width of the specified string + * + * @param str The string to return the width of. + * + * @return The width of the string. + */ + public int stringWidth(String str) + { + char[] buf = new char[str.length()]; + str.getChars(0, str.length(), buf, 0); + + return charsWidth(buf, 0, buf.length); + } + + /** + * Returns the total width of the specified character array. + * + * @param buf The character array containing the data. + * @param offset The offset into the array to start calculating from. + * @param len The total number of bytes to process. + * + * @return The width of the requested characters. + */ + public int charsWidth(char[] buf, int offset, int len) + { + int total_width = 0; + for (int i = offset; i < len; i++) + total_width += charWidth(buf[i]); + return total_width; + } + + /** + * Returns the total width of the specified byte array. + * + * @param buf The byte array containing the data. + * @param offset The offset into the array to start calculating from. + * @param len The total number of bytes to process. + * + * @return The width of the requested characters. + */ + public int bytesWidth(byte[] buf, int offset, int len) + { + int total_width = 0; + for (int i = offset; i < len; i++) + total_width = charWidth((char) buf[i]); + + return total_width; + } + + /** + * Returns the widths of the first 256 characters in the font. + * + * @return The widths of the first 256 characters in the font. + */ + public int[] getWidths() + { + int[] result = new int[256]; + for (char i = 0; i < 256; i++) + result[i] = charWidth(i); + return result; + } + + /** + * Returns a string representation of this object. + * + * @return A string representation of this object. + */ + public String toString() + { + return (this.getClass() + "[font=" + font + ",ascent=" + getAscent() + + ",descent=" + getDescent() + ",height=" + getHeight() + "]"); + } + + // Generic FontRenderContext used when getLineMetrics is called with a + // plain Graphics object. + private static final FontRenderContext gRC = new FontRenderContext(null, + false, + false); + + /** + * Returns a {@link LineMetrics} object constructed with the + * specified text and the {@link FontRenderContext} of the Graphics + * object when it is an instance of Graphics2D or a generic + * FontRenderContext with a null transform, not anti-aliased and not + * using fractional metrics. + * + * @param text The string to calculate metrics from. + * @param g The Graphics object that will be used. + * + * @return A new {@link LineMetrics} object. + */ + public LineMetrics getLineMetrics(String text, Graphics g) + { + return getLineMetrics(text, 0, text.length(), g); + } + + /** + * Returns a {@link LineMetrics} object constructed with the + * specified text and the {@link FontRenderContext} of the Graphics + * object when it is an instance of Graphics2D or a generic + * FontRenderContext with a null transform, not anti-aliased and not + * using fractional metrics. + * + * @param text The string to calculate metrics from. + * @param begin Index of first character in <code>text</code> to measure. + * @param limit Index of last character in <code>text</code> to measure. + * @param g The Graphics object that will be used. + * + * @return A new {@link LineMetrics} object. + * + * @throws IndexOutOfBoundsException if the range [begin, limit] is + * invalid in <code>text</code>. + */ + public LineMetrics getLineMetrics(String text, int begin, int limit, + Graphics g) + { + FontRenderContext rc; + if (g instanceof Graphics2D) + rc = ((Graphics2D) g).getFontRenderContext(); + else + rc = gRC; + return font.getLineMetrics(text, begin, limit, rc); + } + + /** + * Returns a {@link LineMetrics} object constructed with the + * specified text and the {@link FontRenderContext} of the Graphics + * object when it is an instance of Graphics2D or a generic + * FontRenderContext with a null transform, not anti-aliased and not + * using fractional metrics. + * + * @param chars The string to calculate metrics from. + * @param begin Index of first character in <code>text</code> to measure. + * @param limit Index of last character in <code>text</code> to measure. + * @param g The Graphics object that will be used. + * + * @return A new {@link LineMetrics} object. + * + * @throws IndexOutOfBoundsException if the range [begin, limit] is + * invalid in <code>text</code>. + */ + public LineMetrics getLineMetrics(char[] chars, int begin, int limit, + Graphics g) + { + FontRenderContext rc; + if (g instanceof Graphics2D) + rc = ((Graphics2D) g).getFontRenderContext(); + else + rc = gRC; + return font.getLineMetrics(chars, begin, limit, rc); + } + + /** + * Returns a {@link LineMetrics} object constructed with the + * specified text and the {@link FontRenderContext} of the Graphics + * object when it is an instance of Graphics2D or a generic + * FontRenderContext with a null transform, not anti-aliased and not + * using fractional metrics. + * + * @param ci An iterator over the string to calculate metrics from. + * @param begin Index of first character in <code>text</code> to measure. + * @param limit Index of last character in <code>text</code> to measure. + * @param g The Graphics object that will be used. + * + * @return A new {@link LineMetrics} object. + * + * @throws IndexOutOfBoundsException if the range [begin, limit] is + * invalid in <code>text</code>. + */ + public LineMetrics getLineMetrics(CharacterIterator ci, int begin, + int limit, Graphics g) + { + FontRenderContext rc; + if (g instanceof Graphics2D) + rc = ((Graphics2D) g).getFontRenderContext(); + else + rc = gRC; + return font.getLineMetrics(ci, begin, limit, rc); + } + + public Rectangle2D getStringBounds(String str, Graphics context) + { + return font.getStringBounds(str, getFontRenderContext(context)); + } + + public Rectangle2D getStringBounds(String str, int beginIndex, int limit, + Graphics context) + { + return font.getStringBounds(str, beginIndex, limit, + getFontRenderContext(context)); + } + + public Rectangle2D getStringBounds(char[] chars, int beginIndex, int limit, + Graphics context) + { + return font.getStringBounds(chars, beginIndex, limit, + getFontRenderContext(context)); + } + + public Rectangle2D getStringBounds(CharacterIterator ci, int beginIndex, + int limit, Graphics context) + { + return font.getStringBounds(ci, beginIndex, limit, + getFontRenderContext(context)); + } + + private FontRenderContext getFontRenderContext(Graphics context) + { + if (context instanceof Graphics2D) + return ((Graphics2D) context).getFontRenderContext(); + + return gRC; + } +} |