J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1998-2003 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package java.awt.font; |
| 27 | |
| 28 | /** |
| 29 | * The <code>LineMetrics</code> class allows access to the |
| 30 | * metrics needed to layout characters along a line |
| 31 | * and to layout of a set of lines. A <code>LineMetrics</code> |
| 32 | * object encapsulates the measurement information associated |
| 33 | * with a run of text. |
| 34 | * <p> |
| 35 | * Fonts can have different metrics for different ranges of |
| 36 | * characters. The <code>getLineMetrics</code> methods of |
| 37 | * {@link java.awt.Font Font} take some text as an argument |
| 38 | * and return a <code>LineMetrics</code> object describing the |
| 39 | * metrics of the initial number of characters in that text, as |
| 40 | * returned by {@link #getNumChars}. |
| 41 | */ |
| 42 | |
| 43 | |
| 44 | public abstract class LineMetrics { |
| 45 | |
| 46 | |
| 47 | /** |
| 48 | * Returns the number of characters (<code>char</code> values) in the text whose |
| 49 | * metrics are encapsulated by this <code>LineMetrics</code> |
| 50 | * object. |
| 51 | * @return the number of characters (<code>char</code> values) in the text with which |
| 52 | * this <code>LineMetrics</code> was created. |
| 53 | */ |
| 54 | public abstract int getNumChars(); |
| 55 | |
| 56 | /** |
| 57 | * Returns the ascent of the text. The ascent |
| 58 | * is the distance from the baseline |
| 59 | * to the ascender line. The ascent usually represents the |
| 60 | * the height of the capital letters of the text. Some characters |
| 61 | * can extend above the ascender line. |
| 62 | * @return the ascent of the text. |
| 63 | */ |
| 64 | public abstract float getAscent(); |
| 65 | |
| 66 | /** |
| 67 | * Returns the descent of the text. The descent |
| 68 | * is the distance from the baseline |
| 69 | * to the descender line. The descent usually represents |
| 70 | * the distance to the bottom of lower case letters like |
| 71 | * 'p'. Some characters can extend below the descender |
| 72 | * line. |
| 73 | * @return the descent of the text. |
| 74 | */ |
| 75 | public abstract float getDescent(); |
| 76 | |
| 77 | /** |
| 78 | * Returns the leading of the text. The |
| 79 | * leading is the recommended |
| 80 | * distance from the bottom of the descender line to the |
| 81 | * top of the next line. |
| 82 | * @return the leading of the text. |
| 83 | */ |
| 84 | public abstract float getLeading(); |
| 85 | |
| 86 | /** |
| 87 | * Returns the height of the text. The |
| 88 | * height is equal to the sum of the ascent, the |
| 89 | * descent and the leading. |
| 90 | * @return the height of the text. |
| 91 | */ |
| 92 | public abstract float getHeight(); |
| 93 | |
| 94 | /** |
| 95 | * Returns the baseline index of the text. |
| 96 | * The index is one of |
| 97 | * {@link java.awt.Font#ROMAN_BASELINE ROMAN_BASELINE}, |
| 98 | * {@link java.awt.Font#CENTER_BASELINE CENTER_BASELINE}, |
| 99 | * {@link java.awt.Font#HANGING_BASELINE HANGING_BASELINE}. |
| 100 | * @return the baseline of the text. |
| 101 | */ |
| 102 | public abstract int getBaselineIndex(); |
| 103 | |
| 104 | /** |
| 105 | * Returns the baseline offsets of the text, |
| 106 | * relative to the baseline of the text. The |
| 107 | * offsets are indexed by baseline index. For |
| 108 | * example, if the baseline index is |
| 109 | * <code>CENTER_BASELINE</code> then |
| 110 | * <code>offsets[HANGING_BASELINE]</code> is usually |
| 111 | * negative, <code>offsets[CENTER_BASELINE]</code> |
| 112 | * is zero, and <code>offsets[ROMAN_BASELINE]</code> |
| 113 | * is usually positive. |
| 114 | * @return the baseline offsets of the text. |
| 115 | */ |
| 116 | public abstract float[] getBaselineOffsets(); |
| 117 | |
| 118 | /** |
| 119 | * Returns the position of the strike-through line |
| 120 | * relative to the baseline. |
| 121 | * @return the position of the strike-through line. |
| 122 | */ |
| 123 | public abstract float getStrikethroughOffset(); |
| 124 | |
| 125 | /** |
| 126 | * Returns the thickness of the strike-through line. |
| 127 | * @return the thickness of the strike-through line. |
| 128 | */ |
| 129 | public abstract float getStrikethroughThickness(); |
| 130 | |
| 131 | /** |
| 132 | * Returns the position of the underline relative to |
| 133 | * the baseline. |
| 134 | * @return the position of the underline. |
| 135 | */ |
| 136 | public abstract float getUnderlineOffset(); |
| 137 | |
| 138 | /** |
| 139 | * Returns the thickness of the underline. |
| 140 | * @return the thickness of the underline. |
| 141 | */ |
| 142 | public abstract float getUnderlineThickness(); |
| 143 | } |