diff options
Diffstat (limited to 'libjava/java/util/ListIterator.java')
| -rw-r--r-- | libjava/java/util/ListIterator.java | 158 |
1 files changed, 137 insertions, 21 deletions
diff --git a/libjava/java/util/ListIterator.java b/libjava/java/util/ListIterator.java index 8250e2ab01a..8a8d2c74e9d 100644 --- a/libjava/java/util/ListIterator.java +++ b/libjava/java/util/ListIterator.java @@ -1,31 +1,147 @@ -/* Copyright (C) 2000 Free Software Foundation +/* ListIterator.java -- Extended Iterator for iterating over ordered lists + Copyright (C) 1998, 1999 Free Software Foundation, Inc. - This file is part of libgcj. +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., 59 Temple Place, Suite 330, Boston, MA +02111-1307 USA. + +As a special exception, if you link this library with other files to +produce an executable, this library does not by itself cause the +resulting executable to be covered by the GNU General Public License. +This exception does not however invalidate any other reasons why the +executable file might be covered by the GNU General Public License. */ -This software is copyrighted work licensed under the terms of the -Libgcj License. Please consult the file "LIBGCJ_LICENSE" for -details. */ package java.util; /** - * @author Warren Levy <warrenl@cygnus.com> - * @date March 16, 2000. + * An extended version of Iterator to support the extra features of Lists. The + * elements may be accessed in forward or reverse order, elements may be + * replaced as well as removed, and new elements may be inserted, during the + * traversal of the list. */ -/* Written using on-line Java Platform 1.2 API Specification. - * Status: Believed complete and correct. - */ - -// JDK1.2 public interface ListIterator extends Iterator { - public boolean hasNext(); - public Object next(); - public boolean hasPrevious(); - public Object previous(); - public int nextIndex(); - public int previousIndex(); - public void remove(); - public void set(Object o); - public void add(Object o); + /** + * Tests whether there are elements remaining in the list in the forward + * direction. + * + * @return true if there is at least one more element in the list in the + * forward direction, that is, if the next call to next will not throw + * NoSuchElementException. + */ + boolean hasNext(); + + /** + * Tests whether there are elements remaining in the list in the reverse + * direction. + * + * @return true if there is at least one more element in the list in the + * reverse direction, that is, if the next call to previous will not throw + * NoSuchElementException. + */ + boolean hasPrevious(); + + /** + * Obtain the next element in the list in the forward direction. Repeated + * calls to next may be used to iterate over the entire list, or calls to next + * and previous may be used together to go forwards and backwards. Alternating + * calls to next and previous will return the same element. + * + * @return the next element in the list in the forward direction + * @exception NoSuchElementException if there are no more elements + */ + Object next(); + + /** + * Obtain the next element in the list in the reverse direction. Repeated + * calls to previous may be used to iterate backwards over the entire list, or + * calls to next and previous may be used together to go forwards and + * backwards. Alternating calls to next and previous will return the same + * element. + * + * @return the next element in the list in the reverse direction + * @exception NoSuchElementException if there are no more elements + */ + Object previous(); + + /** + * Find the index of the element that would be returned by a call to next. + * + * @return the index of the element that would be returned by a call to next, + * or list.size() if the iterator is at the end of the list. + */ + int nextIndex(); + + /** + * Find the index of the element that would be returned by a call to previous. + * + * @return the index of the element that would be returned by a call to + * previous, or -1 if the iterator is at the beginning of the list. + */ + int previousIndex(); + + /** + * Insert an element into the list at the current position of the iterator. + * The element is inserted in between the element that would be returned by + * previous and the element that would be returned by next. After the + * insertion, a subsequent call to next is unaffected, but a call to + * previous returns the item that was added. This operation is optional, it + * may throw an UnsupportedOperationException. + * + * @param o the object to insert into the list + * @exception ClassCastException the object is of a type which cannot be added + * to this list + * @exception IllegalArgumentException some other aspect of the object stops + * it being added to this list + * @exception UnsupportedOperationException if this ListIterator does not + * support the add operation + */ + void add(Object o); + + /** + * Remove from the list the element last returned by a call to next or + * previous. This method may only be called if neither add nor remove have + * been called since the last call to next or previous. This operation is + * optional, it may throw an UnsupportedOperationException. + * + * @exception IllegalStateException if neither next or previous have been + * called, or if add or remove has been called since the last call to next + * or previous. + * @exception UnsupportedOperationException if this ListIterator does not + * support the remove operation. + */ + void remove(); + + /** + * Replace the element last returned by a call to next or previous with a + * given object. This method may only be called if neither add nor remove have + * been called since the last call to next or previous. This operation is + * optional, it may throw an UnsupportedOperationException. + * + * @param o the object to replace the element with + * @exception ClassCastException the object is of a type which cannot be added + * to this list + * @exception IllegalArgumentException some other aspect of the object stops + * it being added to this list + * @exception IllegalStateException if neither next or previous have been + * called, or if add or remove has been called since the last call to next + * or previous. + * @exception UnsupportedOperationException if this ListIterator does not + * support the set operation. + */ + void set(Object o); } |