Java tutorial
/* * Copyright (c) 1998, 2003, 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. */ package java.awt.font; /** * The {@code LineMetrics} class allows access to the * metrics needed to layout characters along a line * and to layout of a set of lines. A {@code LineMetrics} * object encapsulates the measurement information associated * with a run of text. * <p> * Fonts can have different metrics for different ranges of * characters. The {@code getLineMetrics} methods of * {@link java.awt.Font Font} take some text as an argument * and return a {@code LineMetrics} object describing the * metrics of the initial number of characters in that text, as * returned by {@link #getNumChars}. */ public abstract class LineMetrics { /** * Returns the number of characters ({@code char} values) in the text whose * metrics are encapsulated by this {@code LineMetrics} * object. * @return the number of characters ({@code char} values) in the text with which * this {@code LineMetrics} was created. */ public abstract int getNumChars(); /** * Returns the ascent of the text. The ascent * is the distance from the baseline * to the ascender line. The ascent usually represents the * the height of the capital letters of the text. Some characters * can extend above the ascender line. * @return the ascent of the text. */ public abstract float getAscent(); /** * Returns the descent of the text. The descent * is the distance from the baseline * to the descender line. The descent usually represents * the distance to the bottom of lower case letters like * 'p'. Some characters can extend below the descender * line. * @return the descent of the text. */ public abstract float getDescent(); /** * Returns the leading of the text. The * leading is the recommended * distance from the bottom of the descender line to the * top of the next line. * @return the leading of the text. */ public abstract float getLeading(); /** * Returns the height of the text. The * height is equal to the sum of the ascent, the * descent and the leading. * @return the height of the text. */ public abstract float getHeight(); /** * Returns the baseline index of the text. * The index is one of * {@link java.awt.Font#ROMAN_BASELINE ROMAN_BASELINE}, * {@link java.awt.Font#CENTER_BASELINE CENTER_BASELINE}, * {@link java.awt.Font#HANGING_BASELINE HANGING_BASELINE}. * @return the baseline of the text. */ public abstract int getBaselineIndex(); /** * Returns the baseline offsets of the text, * relative to the baseline of the text. The * offsets are indexed by baseline index. For * example, if the baseline index is * {@code CENTER_BASELINE} then * {@code offsets[HANGING_BASELINE]} is usually * negative, {@code offsets[CENTER_BASELINE]} * is zero, and {@code offsets[ROMAN_BASELINE]} * is usually positive. * @return the baseline offsets of the text. */ public abstract float[] getBaselineOffsets(); /** * Returns the position of the strike-through line * relative to the baseline. * @return the position of the strike-through line. */ public abstract float getStrikethroughOffset(); /** * Returns the thickness of the strike-through line. * @return the thickness of the strike-through line. */ public abstract float getStrikethroughThickness(); /** * Returns the position of the underline relative to * the baseline. * @return the position of the underline. */ public abstract float getUnderlineOffset(); /** * Returns the thickness of the underline. * @return the thickness of the underline. */ public abstract float getUnderlineThickness(); }