Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2008 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package org.eclipse.swt.custom; import org.eclipse.swt.*; /** * Instances of this class represent bullets in the <code>StyledText</code>. * <p> * The hashCode() method in this class uses the values of the public * fields to compute the hash value. When storing instances of the * class in hashed collections, do not modify these fields after the * object has been inserted. * </p> * <p> * Application code does <em>not</em> need to explicitly release the * resources managed by each instance when those instances are no longer * required, and thus no <code>dispose()</code> method is provided. * </p> * * @see StyledText#setLineBullet(int, int, Bullet) * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> * * @since 3.2 */ public class Bullet { /** * The bullet type. Possible values are: * <ul> * <li><code>ST.BULLET_DOT</code></li> * <li><code>ST.BULLET_NUMBER</code></li> * <li><code>ST.BULLET_LETTER_LOWER</code></li> * <li><code>ST.BULLET_LETTER_UPPER</code></li> * <li><code>ST.BULLET_TEXT</code></li> * <li><code>ST.BULLET_CUSTOM</code></li> * </ul> */ public int type; /** * The bullet style. */ public StyleRange style; /** * The bullet text. */ public String text; int[] linesIndices; int count; /** * Create a new bullet with the specified style, and type <code>ST.BULLET_DOT</code>. * The style must have a glyph metrics set. * * @param style the style * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT when the style or the glyph metrics are null</li> * </ul> */ public Bullet(StyleRange style) { this(ST.BULLET_DOT, style); } /** * Create a new bullet the specified style and type. * The style must have a glyph metrics set. * * @param type the bullet type * @param style the style * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT when the style or the glyph metrics are null</li> * </ul> */ public Bullet(int type, StyleRange style) { if (style == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); if (style.metrics == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); this.type = type; this.style = style; } void addIndices(int startLine, int lineCount) { if (linesIndices == null) { linesIndices = new int[lineCount]; count = lineCount; for (int i = 0; i < lineCount; i++) linesIndices[i] = startLine + i; } else { int modifyStart = 0; while (modifyStart < count) { if (startLine <= linesIndices[modifyStart]) break; modifyStart++; } int modifyEnd = modifyStart; while (modifyEnd < count) { if (startLine + lineCount <= linesIndices[modifyEnd]) break; modifyEnd++; } int newSize = modifyStart + lineCount + count - modifyEnd; if (newSize > linesIndices.length) { int[] newLinesIndices = new int[newSize]; System.arraycopy(linesIndices, 0, newLinesIndices, 0, count); linesIndices = newLinesIndices; } System.arraycopy(linesIndices, modifyEnd, linesIndices, modifyStart + lineCount, count - modifyEnd); for (int i = 0; i < lineCount; i++) linesIndices[modifyStart + i] = startLine + i; count = newSize; } } int indexOf(int lineIndex) { for (int i = 0; i < count; i++) { if (linesIndices[i] == lineIndex) return i; } return -1; } @Override public int hashCode() { return style.hashCode() ^ type; } int[] removeIndices(int startLine, int replaceLineCount, int newLineCount, boolean update) { if (count == 0) return null; if (startLine > linesIndices[count - 1]) return null; int endLine = startLine + replaceLineCount; int delta = newLineCount - replaceLineCount; for (int i = 0; i < count; i++) { int index = linesIndices[i]; if (startLine <= index) { int j = i; while (j < count) { if (linesIndices[j] >= endLine) break; j++; } if (update) { for (int k = j; k < count; k++) linesIndices[k] += delta; } int[] redrawLines = new int[count - j]; System.arraycopy(linesIndices, j, redrawLines, 0, count - j); System.arraycopy(linesIndices, j, linesIndices, i, count - j); count -= (j - i); return redrawLines; } } for (int i = 0; i < count; i++) linesIndices[i] += delta; return null; } int size() { return count; } }