| /* |
| * Copyright (c) 1996, 2013, 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. |
| */ |
| |
| /* |
| * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved |
| * (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved |
| * |
| * The original version of this source code and documentation |
| * is copyrighted and owned by Taligent, Inc., a wholly-owned |
| * subsidiary of IBM. These materials are provided under terms |
| * of a License Agreement between Taligent and Sun. This technology |
| * is protected by multiple US and International patents. |
| * |
| * This notice and attribution to Taligent may not be removed. |
| * Taligent is a registered trademark of Taligent, Inc. |
| * |
| */ |
| |
| package java.text; |
| |
| |
| /** |
| * This interface defines a protocol for bidirectional iteration over text. |
| * The iterator iterates over a bounded sequence of characters. Characters |
| * are indexed with values beginning with the value returned by getBeginIndex() and |
| * continuing through the value returned by getEndIndex()-1. |
| * <p> |
| * Iterators maintain a current character index, whose valid range is from |
| * getBeginIndex() to getEndIndex(); the value getEndIndex() is included to allow |
| * handling of zero-length text ranges and for historical reasons. |
| * The current index can be retrieved by calling getIndex() and set directly |
| * by calling setIndex(), first(), and last(). |
| * <p> |
| * The methods previous() and next() are used for iteration. They return DONE if |
| * they would move outside the range from getBeginIndex() to getEndIndex() -1, |
| * signaling that the iterator has reached the end of the sequence. DONE is |
| * also returned by other methods to indicate that the current index is |
| * outside this range. |
| * |
| * <P>Examples:<P> |
| * |
| * Traverse the text from start to finish |
| * <pre>{@code |
| * public void traverseForward(CharacterIterator iter) { |
| * for(char c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) { |
| * processChar(c); |
| * } |
| * } |
| * }</pre> |
| * |
| * Traverse the text backwards, from end to start |
| * <pre>{@code |
| * public void traverseBackward(CharacterIterator iter) { |
| * for(char c = iter.last(); c != CharacterIterator.DONE; c = iter.previous()) { |
| * processChar(c); |
| * } |
| * } |
| * }</pre> |
| * |
| * Traverse both forward and backward from a given position in the text. |
| * Calls to notBoundary() in this example represents some |
| * additional stopping criteria. |
| * <pre>{@code |
| * public void traverseOut(CharacterIterator iter, int pos) { |
| * for (char c = iter.setIndex(pos); |
| * c != CharacterIterator.DONE && notBoundary(c); |
| * c = iter.next()) { |
| * } |
| * int end = iter.getIndex(); |
| * for (char c = iter.setIndex(pos); |
| * c != CharacterIterator.DONE && notBoundary(c); |
| * c = iter.previous()) { |
| * } |
| * int start = iter.getIndex(); |
| * processSection(start, end); |
| * } |
| * }</pre> |
| * |
| * @since 1.1 |
| * @see StringCharacterIterator |
| * @see AttributedCharacterIterator |
| */ |
| |
| public interface CharacterIterator extends Cloneable |
| { |
| |
| /** |
| * Constant that is returned when the iterator has reached either the end |
| * or the beginning of the text. The value is '\\uFFFF', the "not a |
| * character" value which should not occur in any valid Unicode string. |
| */ |
| public static final char DONE = '\uFFFF'; |
| |
| /** |
| * Sets the position to getBeginIndex() and returns the character at that |
| * position. |
| * @return the first character in the text, or DONE if the text is empty |
| * @see #getBeginIndex() |
| */ |
| public char first(); |
| |
| /** |
| * Sets the position to getEndIndex()-1 (getEndIndex() if the text is empty) |
| * and returns the character at that position. |
| * @return the last character in the text, or DONE if the text is empty |
| * @see #getEndIndex() |
| */ |
| public char last(); |
| |
| /** |
| * Gets the character at the current position (as returned by getIndex()). |
| * @return the character at the current position or DONE if the current |
| * position is off the end of the text. |
| * @see #getIndex() |
| */ |
| public char current(); |
| |
| /** |
| * Increments the iterator's index by one and returns the character |
| * at the new index. If the resulting index is greater or equal |
| * to getEndIndex(), the current index is reset to getEndIndex() and |
| * a value of DONE is returned. |
| * @return the character at the new position or DONE if the new |
| * position is off the end of the text range. |
| */ |
| public char next(); |
| |
| /** |
| * Decrements the iterator's index by one and returns the character |
| * at the new index. If the current index is getBeginIndex(), the index |
| * remains at getBeginIndex() and a value of DONE is returned. |
| * @return the character at the new position or DONE if the current |
| * position is equal to getBeginIndex(). |
| */ |
| public char previous(); |
| |
| /** |
| * Sets the position to the specified position in the text and returns that |
| * character. |
| * @param position the position within the text. Valid values range from |
| * getBeginIndex() to getEndIndex(). An IllegalArgumentException is thrown |
| * if an invalid value is supplied. |
| * @return the character at the specified position or DONE if the specified position is equal to getEndIndex() |
| */ |
| public char setIndex(int position); |
| |
| /** |
| * Returns the start index of the text. |
| * @return the index at which the text begins. |
| */ |
| public int getBeginIndex(); |
| |
| /** |
| * Returns the end index of the text. This index is the index of the first |
| * character following the end of the text. |
| * @return the index after the last character in the text |
| */ |
| public int getEndIndex(); |
| |
| /** |
| * Returns the current index. |
| * @return the current index. |
| */ |
| public int getIndex(); |
| |
| /** |
| * Create a copy of this iterator |
| * @return A copy of this |
| */ |
| public Object clone(); |
| |
| } |