/*
* Copyright 2003-2011 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jetbrains.mps.util;
import java.util.AbstractSet;
import java.util.BitSet;
import java.util.Iterator;
import java.util.NoSuchElementException;
public abstract class IndexableObjectSet<E> extends AbstractSet<E> {
private BitSet myBitSet;
protected IndexableObjectSet(int size) {
this(size, false);
}
protected IndexableObjectSet(int size, boolean full) {
myBitSet = new BitSet(size);
if (full) {
myBitSet.set(0, size);
}
}
protected abstract int getIndex(E e);
protected abstract E getObject(int index);
@Override
public Iterator<E> iterator() {
return new Iterator<E>() {
private int myCurrent = 0;
@Override
public boolean hasNext() {
return myBitSet.nextSetBit(myCurrent) != -1;
}
@Override
public E next() {
int nextSetBit = myBitSet.nextSetBit(myCurrent);
if (nextSetBit == -1) throw new NoSuchElementException();
myCurrent = nextSetBit + 1;
return getObject(nextSetBit);
}
@Override
public void remove() {
if (myCurrent == 0) throw new IllegalStateException();
myBitSet.set(myCurrent - 1, false);
}
};
}
@Override
public int size() {
int result = 0;
for (int i = 0; i < myBitSet.size(); i++) {
if (myBitSet.get(i)) {
result++;
}
}
return result;
}
@Override
public boolean isEmpty() {
return myBitSet.isEmpty();
}
@Override
public boolean contains(Object o) {
int index = getIndex((E) o);
if (index == -1) return false;
return myBitSet.get(index);
}
@Override
public boolean add(E e) {
int index = getIndex(e);
if (index == -1) throw new IllegalArgumentException();
boolean was = myBitSet.get(index);
myBitSet.set(index);
return !was;
}
@Override
public boolean remove(Object o) {
int index = getIndex((E) o);
if (index == -1) throw new IllegalArgumentException();
boolean contained = myBitSet.get(index);
myBitSet.set(index, false);
return contained;
}
public void add(int index) {
myBitSet.set(index);
}
public void remove(int index) {
myBitSet.set(index, false);
}
public void addAll(IndexableObjectSet<E> set) {
myBitSet.or(set.myBitSet);
}
public void retainAll(IndexableObjectSet<E> set) {
myBitSet.and(set.myBitSet);
}
public boolean contains(int varId) {
return myBitSet.get(varId);
}
@Override
public void clear() {
myBitSet.clear();
}
@Override
public int hashCode() {
return myBitSet.hashCode();
}
@Override
public boolean equals(Object o) {
if (o instanceof IndexableObjectSet) {
IndexableObjectSet vs = (IndexableObjectSet) o;
return vs.myBitSet.equals(myBitSet);
}
return super.equals(o);
}
}