Mega Code Archive
Extend AbstractSet to Create Simple Set
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/* SimpleSet Copyright (C) 1998-2002 Jochen Hoenicke.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program 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 Lesser General Public License
* along with this program; see the file COPYING.LESSER. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: SimpleSet.java.in,v 1.1.2.1 2002/05/28 17:34:24 hoenicke Exp $
*/
import java.util.AbstractSet;
import java.util.Iterator;
public class SimpleSet extends AbstractSet implements Cloneable
{
Object[] elementObjects;
int count = 0;
public SimpleSet() {
this(2);
}
public SimpleSet(int initialSize) {
elementObjects = new Object[initialSize];
}
public int size() {
return count;
}
public boolean add(Object element) {
if (element == null)
throw new NullPointerException();
for (int i=0; i< count; i++) {
if (element.equals(elementObjects[i]))
return false;
}
if (count == elementObjects.length) {
Object[] newArray = new Object[(count+1)*3/2];
System.arraycopy(elementObjects,0,newArray,0,count);
elementObjects = newArray;
}
elementObjects[count++] = element;
return true;
}
public Object clone() {
try {
SimpleSet other = (SimpleSet) super.clone();
other.elementObjects = (Object[]) elementObjects.clone();
return other;
} catch (CloneNotSupportedException ex) {
}
}
public Iterator iterator() {
return new Iterator() {
int pos = 0;
public boolean hasNext() {
return pos < count;
}
public Object next() {
return elementObjects[pos++];
}
public void remove() {
if (pos < count)
System.arraycopy(elementObjects, pos,
elementObjects, pos-1, count - pos);
count--;
pos--;
}
};
}
}
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