/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.jikesrvm.util;
/**
* A hash set with entirely immutable buckets. It doesn't correctly support
* remove, so use with care.
*/
public final class ImmutableEntryHashSetRVM<T> extends AbstractHashSetRVM<T> {
static final class Bucket<T> extends AbstractBucket<T> {
private final T key;
private final AbstractBucket<T> next;
Bucket(T key, AbstractBucket<T> next) {
this.key = key;
this.next = next;
}
@Override
AbstractBucket<T> setNext(AbstractBucket<T> next) {
if (this.next == next) {
return this;
} else {
return new Bucket<T>(key, next);
}
}
@Override
AbstractBucket<T> getNext() {
return next;
}
@Override
T getKey() {
return key;
}
}
@Override
AbstractBucket<T> createNewBucket(T key, AbstractBucket<T> next) {
return new Bucket<T>(key, next);
}
public ImmutableEntryHashSetRVM() {
super(DEFAULT_SIZE);
}
public ImmutableEntryHashSetRVM(int size) {
super(size);
}
@Override
public void remove(T key) {
throw new UnsupportedOperationException();
}
}