/*
* 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 org.jctools_voltpatches.queues.atomic;
import java.util.AbstractQueue;
import java.util.Iterator;
import java.util.concurrent.atomic.AtomicReferenceArray;
import org.jctools_voltpatches.util.Pow2;
abstract class AtomicReferenceArrayQueue<E> extends AbstractQueue<E> {
protected final AtomicReferenceArray<E> buffer;
protected final int mask;
public AtomicReferenceArrayQueue(int capacity) {
int actualCapacity = Pow2.roundToPowerOfTwo(capacity);
this.mask = actualCapacity - 1;
this.buffer = new AtomicReferenceArray<E>(actualCapacity);
}
@Override
public Iterator<E> iterator() {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
// we have to test isEmpty because of the weaker poll() guarantee
while (poll() != null || !isEmpty())
;
}
protected final int calcElementOffset(long index, int mask) {
return (int)index & mask;
}
protected final int calcElementOffset(long index) {
return (int)index & mask;
}
protected final E lvElement(AtomicReferenceArray<E> buffer, int offset) {
return buffer.get(offset);
}
protected final E lpElement(AtomicReferenceArray<E> buffer, int offset) {
return buffer.get(offset); // no weaker form available
}
protected final E lpElement(int offset) {
return buffer.get(offset); // no weaker form available
}
protected final void spElement(AtomicReferenceArray<E> buffer, int offset, E value) {
buffer.lazySet(offset, value); // no weaker form available
}
protected final void spElement(int offset, E value) {
buffer.lazySet(offset, value); // no weaker form available
}
protected final void soElement(AtomicReferenceArray<E> buffer, int offset, E value) {
buffer.lazySet(offset, value);
}
protected final void soElement(int offset, E value) {
buffer.lazySet(offset, value);
}
protected final void svElement(AtomicReferenceArray<E> buffer, int offset, E value) {
buffer.set(offset, value);
}
protected final E lvElement(int offset) {
return lvElement(buffer, offset);
}
}