/*
* Copyright 2015, 2016 Tagir Valeev
*
* 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 one.util.streamex;
import java.util.Spliterator;
import java.util.function.Consumer;
import one.util.streamex.StreamExInternals.TailSpliterator;
/**
* @author Tagir Valeev
*
* @param <T> type of the elements
*/
/* package */class TailConcatSpliterator<T> implements TailSpliterator<T> {
private Spliterator<T> left, right;
private int characteristics;
private long size;
@SuppressWarnings("unchecked")
public TailConcatSpliterator(Spliterator<? extends T> left, Spliterator<? extends T> right) {
this.left = (Spliterator<T>) left;
this.right = (Spliterator<T>) right;
this.characteristics = left.characteristics() & right.characteristics() & (ORDERED | SIZED | SUBSIZED);
this.size = left.estimateSize() + right.estimateSize();
if (this.size < 0) {
this.size = Long.MAX_VALUE;
this.characteristics &= (~SIZED) & (~SUBSIZED);
}
}
@Override
public boolean tryAdvance(Consumer<? super T> action) {
if (left != null) {
if (left.tryAdvance(action)) {
if (size > 0 && size != Long.MAX_VALUE)
size--;
return true;
}
left = null;
}
if(right != null)
right = TailSpliterator.tryAdvanceWithTail(right, action);
return right != null;
}
@Override
public Spliterator<T> tryAdvanceOrTail(Consumer<? super T> action) {
if (left == null || !left.tryAdvance(action)) {
Spliterator<T> s = right;
right = null;
return s;
}
if (size > 0 && size != Long.MAX_VALUE)
size--;
return this;
}
@Override
public void forEachRemaining(Consumer<? super T> action) {
if (left != null)
left.forEachRemaining(action);
if(right != null)
TailSpliterator.forEachWithTail(right, action);
}
@Override
public Spliterator<T> forEachOrTail(Consumer<? super T> action) {
if (left != null)
left.forEachRemaining(action);
Spliterator<T> s = right;
right = null;
return s;
}
@Override
public Spliterator<T> trySplit() {
if (left == null)
return right.trySplit();
Spliterator<T> s = left;
left = null;
return s;
}
@Override
public long estimateSize() {
if (left == null)
return right == null ? 0 : right.estimateSize();
return size;
}
@Override
public int characteristics() {
return characteristics;
}
}