J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2006 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 javax.swing.text; |
| 27 | |
| 28 | import java.text.BreakIterator; |
| 29 | import java.text.CharacterIterator; |
| 30 | import java.text.StringCharacterIterator; |
| 31 | import java.util.Arrays; |
| 32 | |
| 33 | /** |
| 34 | * A simple whitespace-based BreakIterator implementation. |
| 35 | * |
| 36 | * @author Sergey Groznyh |
| 37 | */ |
| 38 | class WhitespaceBasedBreakIterator extends BreakIterator { |
| 39 | private char[] text = new char[0]; |
| 40 | private int[] breaks = new int[] { 0 } ; |
| 41 | private int pos = 0; |
| 42 | |
| 43 | /** |
| 44 | * Calculate break positions eagerly parallel to reading text. |
| 45 | */ |
| 46 | public void setText(CharacterIterator ci) { |
| 47 | int begin = ci.getBeginIndex(); |
| 48 | text = new char[ci.getEndIndex() - begin]; |
| 49 | int[] breaks0 = new int[text.length + 1]; |
| 50 | int brIx = 0; |
| 51 | breaks0[brIx++] = begin; |
| 52 | |
| 53 | int charIx = 0; |
| 54 | boolean inWs = false; |
| 55 | for (char c = ci.first(); c != CharacterIterator.DONE; c = ci.next()) { |
| 56 | text[charIx] = c; |
| 57 | boolean ws = Character.isWhitespace(c); |
| 58 | if (inWs && !ws) { |
| 59 | breaks0[brIx++] = charIx + begin; |
| 60 | } |
| 61 | inWs = ws; |
| 62 | charIx++; |
| 63 | } |
| 64 | if (text.length > 0) { |
| 65 | breaks0[brIx++] = text.length + begin; |
| 66 | } |
| 67 | System.arraycopy(breaks0, 0, breaks = new int[brIx], 0, brIx); |
| 68 | } |
| 69 | |
| 70 | public CharacterIterator getText() { |
| 71 | return new StringCharacterIterator(new String(text)); |
| 72 | } |
| 73 | |
| 74 | public int first() { |
| 75 | return breaks[pos = 0]; |
| 76 | } |
| 77 | |
| 78 | public int last() { |
| 79 | return breaks[pos = breaks.length - 1]; |
| 80 | } |
| 81 | |
| 82 | public int current() { |
| 83 | return breaks[pos]; |
| 84 | } |
| 85 | |
| 86 | public int next() { |
| 87 | return (pos == breaks.length - 1 ? DONE : breaks[++pos]); |
| 88 | } |
| 89 | |
| 90 | public int previous() { |
| 91 | return (pos == 0 ? DONE : breaks[--pos]); |
| 92 | } |
| 93 | |
| 94 | public int next(int n) { |
| 95 | return checkhit(pos + n); |
| 96 | } |
| 97 | |
| 98 | public int following(int n) { |
| 99 | return adjacent(n, 1); |
| 100 | } |
| 101 | |
| 102 | public int preceding(int n) { |
| 103 | return adjacent(n, -1); |
| 104 | } |
| 105 | |
| 106 | private int checkhit(int hit) { |
| 107 | if ((hit < 0) || (hit >= breaks.length)) { |
| 108 | return DONE; |
| 109 | } else { |
| 110 | return breaks[pos = hit]; |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | private int adjacent(int n, int bias) { |
| 115 | int hit = Arrays.binarySearch(breaks, n); |
| 116 | int offset = (hit < 0 ? (bias < 0 ? -1 : -2) : 0); |
| 117 | return checkhit(Math.abs(hit) + bias + offset); |
| 118 | } |
| 119 | } |