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Diffstat (limited to 'libjava/classpath/java/text/CharacterIterator.java')
-rw-r--r-- | libjava/classpath/java/text/CharacterIterator.java | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/libjava/classpath/java/text/CharacterIterator.java b/libjava/classpath/java/text/CharacterIterator.java new file mode 100644 index 00000000000..6b3f951d1fb --- /dev/null +++ b/libjava/classpath/java/text/CharacterIterator.java @@ -0,0 +1,144 @@ +/* CharacterIterator.java -- Iterate over a character range + Copyright (C) 1998, 2001 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.text; + +/** + * This interface defines a mechanism for iterating over a range of + * characters. For a given range of text, a beginning and ending index, + * as well as a current index are defined. These values can be queried + * by the methods in this interface. Additionally, various methods allow + * the index to be set. + * + * @author Aaron M. Renn (arenn@urbanophile.com) + */ +public interface CharacterIterator extends Cloneable +{ + /** + * This is a special constant value that is returned when the beginning or + * end of the character range has been reached. + */ + char DONE = '\uFFFF'; + + /** + * This method returns the character at the current index position + * + * @return The character at the current index position. + */ + char current(); + + /** + * This method increments the current index and then returns the character + * at the new index value. If the index is already at <code>getEndIndex() - 1</code>, + * it will not be incremented. + * + * @return The character at the position of the incremented index value, + * or <code>DONE</code> if the index has reached getEndIndex() - 1 + */ + char next(); + + /** + * This method decrements the current index and then returns the character + * at the new index value. If the index value is already at the beginning + * index, it will not be decremented. + * + * @return The character at the position of the decremented index value, + * or <code>DONE</code> if index was already equal to the beginning index value. + */ + char previous(); + + /** + * This method sets the index value to the beginning of the range and returns + * the character there. + * + * @return The character at the beginning of the range, or <code>DONE</code> if the range is empty. + */ + char first(); + + /** + * This method sets the index value to <code>getEndIndex() - 1</code> and + * returns the character there. If the range is empty, then the index value + * will be set equal to the beginning index. + * + * @return The character at the end of the range, or <code>DONE</code> if the range is empty. + */ + char last(); + + /** + * This method returns the current value of the index. + * + * @return The current index value + */ + int getIndex(); + + /** + * This method sets the value of the index to the specified value, then + * returns the character at that position. + * + * @param index The new index value. + * + * @return The character at the new index value or <code>DONE</code> if the index value is equal to <code>getEndIndex</code>. + */ + char setIndex (int index) throws IllegalArgumentException; + + /** + * This method returns the character position of the first character in the + * range. + * + * @return The index of the first character in the range. + */ + int getBeginIndex(); + + /** + * This method returns the character position of the end of the text range. + * This will actually be the index of the first character following the + * end of the range. In the event the text range is empty, this will be + * equal to the first character in the range. + * + * @return The index of the end of the range. + */ + int getEndIndex(); + + /** + * This method creates a copy of this <code>CharacterIterator</code>. + * + * @return A copy of this <code>CharacterIterator</code>. + */ + Object clone(); + +} // interface CharacterIterator |