/* Copyright (c) 2001-2009, The HSQL Development Group
* 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 HSQL Development Group 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 HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
* 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 org.hsqldb_voltpatches.lib;
import org.hsqldb_voltpatches.store.BaseHashMap;
/**
* This class does not store null keys.
*
* @author Fred Toussi (fredt@users dot sourceforge.net)
* @version 1.9.0
* @since 1.7.2
*/
public class HashSet extends BaseHashMap implements Set {
public HashSet() {
this(8);
}
public HashSet(int initialCapacity) throws IllegalArgumentException {
super(initialCapacity, BaseHashMap.objectKeyOrValue, BaseHashMap.noKeyOrValue,
false);
}
public boolean contains(Object key) {
return super.containsKey(key);
}
public boolean containsAll(Collection col) {
Iterator it = col.iterator();
while (it.hasNext()) {
if (contains(it.next())) {
continue;
}
return false;
}
return true;
}
public Object get(Object key) {
int lookup = getLookup(key, key.hashCode());
if (lookup < 0) {
return null;
} else {
return objectKeyTable[lookup];
}
}
public boolean add(Object key) {
int oldSize = size();
super.addOrRemove(0, 0, key, null, false);
return oldSize != size();
}
public boolean addAll(Collection c) {
int oldSize = size();
Iterator it = c.iterator();
while (it.hasNext()) {
add(it.next());
}
return oldSize != size();
}
public boolean addAll(Object[] keys) {
boolean changed = false;
for (int i = 0; i < keys.length; i++) {
if (add(keys[i])) {
changed = true;
}
}
return changed;
}
public boolean remove(Object key) {
int oldSize = size();
super.removeObject(key, false);
return oldSize != size();
}
public boolean removeAll(Collection c) {
Iterator it = c.iterator();
boolean result = true;
while (it.hasNext()) {
result &= remove(it.next());
}
return result;
}
public Object[] toArray(Object[] a) {
if (a == null || a.length < size()) {
a = new Object[size()];
}
Iterator it = iterator();
for (int i = 0; it.hasNext(); i++) {
a[i] = it.next();
}
return a;
}
public Iterator iterator() {
return new BaseHashIterator(true);
}
/**
* Returns a String like "[Drei, zwei, Eins]", exactly like
* java.util.HashSet.
*/
public String toString() {
Iterator it = iterator();
StringBuffer sb = new StringBuffer();
while (it.hasNext()) {
if (sb.length() > 0) {
sb.append(", ");
} else {
sb.append('[');
}
sb.append(it.next());
}
return sb.toString() + ']';
}
}