/*
* Copyright (c) 2008, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.twelvemonkeys.util;
import java.io.
Serializable;
import java.util.*;
/**
* Generic map and linked list implementation of the {@code Set} interface,
* with predictable iteration order.
* <p>
* Resembles {@code LinkedHashSet} from JDK 1.4+, but is backed by a generic
* {@code LinkedMap}, rather than implementing a particular algoritm.
* <p/>
* @see LinkedMap
*
* @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>
* @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/util/LinkedSet.java#1 $
*/
public class
LinkedSet<E> extends
AbstractSet<E> implements
Set<E>,
Cloneable,
Serializable {
private final static
Object DUMMY = new
Object();
private final
Map<E,
Object>
map;
public
LinkedSet() {
map = new
LinkedMap<E,
Object>();
}
public
LinkedSet(
Collection<E>
pCollection) {
this();
addAll(
pCollection);
}
public boolean
addAll(
Collection<? extends E>
pCollection) {
boolean
changed = false;
for (E
value :
pCollection) {
if (
add(
value) && !
changed) {
changed = true;
}
}
return
changed;
}
public boolean
add(E
pValue) {
return
map.
put(
pValue,
DUMMY) == null;
}
public int
size() {
return
map.
size();
}
public
Iterator<E>
iterator() {
return
map.
keySet().
iterator();
}
}