| /* |
| * Copyright (c) 2007, 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. |
| * |
| * 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. |
| */ |
| |
| import java.text.BreakIterator; |
| import java.text.CharacterIterator; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.NoSuchElementException; |
| |
| public class MirroredBreakIterator extends BreakIterator { |
| private final List<Integer> boundaries; |
| private int charIndex; |
| private int boundaryIndex; |
| |
| MirroredBreakIterator(BreakIterator bi) { |
| List<Integer> b = new ArrayList<Integer>(); |
| int i = bi.first(); |
| charIndex = i; |
| for (; i != DONE; i = bi.next()) { |
| b.add(i); |
| } |
| boundaries = Collections.unmodifiableList(b); |
| } |
| |
| @Override |
| public Object clone() { |
| try { |
| return super.clone(); |
| } catch (Exception e) { |
| throw new RuntimeException("clone failed", e); |
| } |
| } |
| |
| @Override |
| public int first() { |
| return changeIndices(0); |
| } |
| |
| @Override |
| public int last() { |
| return changeIndices(boundaries.size() - 1); |
| } |
| |
| @Override |
| public int next(int n) { |
| if (n == 0) { |
| return current(); |
| } |
| int newBoundary = boundaryIndex + n; |
| if (newBoundary < 0) { |
| first(); |
| return DONE; |
| } |
| if (newBoundary > lastBoundary()) { |
| last(); |
| return DONE; |
| } |
| return changeIndices(newBoundary); |
| } |
| |
| @Override |
| public int next() { |
| if (boundaryIndex == lastBoundary()) { |
| return DONE; |
| } |
| return changeIndices(boundaryIndex + 1); |
| } |
| |
| @Override |
| public int previous() { |
| if (boundaryIndex == 0) { |
| return DONE; |
| } |
| return changeIndices(boundaryIndex - 1); |
| } |
| |
| @Override |
| public int following(int offset) { |
| validateOffset(offset); |
| for (int b = 0; b <= lastBoundary(); b++) { |
| int i = boundaries.get(b); |
| if (i > offset) { |
| return changeIndices(i, b); |
| } |
| } |
| return DONE; |
| } |
| |
| @Override |
| public int preceding(int offset) { |
| validateOffset(offset); |
| for (int b = lastBoundary(); b >= 0; b--) { |
| int i = boundaries.get(b); |
| if (i < offset) { |
| return changeIndices(i, b); |
| } |
| } |
| return DONE; |
| } |
| |
| @Override |
| public boolean isBoundary(int offset) { |
| // Call the default impelementation in BreakIterator |
| return super.isBoundary(offset); |
| } |
| |
| @Override |
| public int current() { |
| return charIndex; |
| } |
| |
| @Override |
| public CharacterIterator getText() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public void setText(CharacterIterator newText) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| private int lastBoundary() { |
| return boundaries.size() - 1; |
| } |
| |
| private int changeIndices(int newCharIndex, int newBoundary) { |
| boundaryIndex = newBoundary; |
| return charIndex = newCharIndex; |
| } |
| |
| private int changeIndices(int newBoundary) { |
| try { |
| return changeIndices(boundaries.get(newBoundary), newBoundary); |
| } catch (IndexOutOfBoundsException e) { |
| throw new IllegalArgumentException(e); |
| } |
| } |
| |
| private void validateOffset(int offset) { |
| if (offset < boundaries.get(0) || offset > boundaries.get(lastBoundary())) { |
| throw new IllegalArgumentException(); |
| } |
| } |
| } |