--- /dev/null
+/* 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;
+ }
+}
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