com.metamx.common.guava.nary.BinaryTransformIterator Maven / Gradle / Ivy
/*
* Copyright 2011,2012 Metamarkets Group Inc.
*
* 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 com.metamx.common.guava.nary;
import java.util.Iterator;
import java.util.NoSuchElementException;
/**
*/
public class BinaryTransformIterator implements Iterator
{
public static BinaryTransformIterator create(
Iterator lhs,
Iterator rhs,
BinaryFn fn
)
{
return new BinaryTransformIterator<>(lhs, rhs, fn);
}
private final Iterator lhsIter;
private final Iterator rhsIter;
private final BinaryFn binaryFn;
public BinaryTransformIterator(Iterator lhsIter, Iterator rhsIter, BinaryFn binaryFn)
{
this.lhsIter = lhsIter;
this.rhsIter = rhsIter;
this.binaryFn = binaryFn;
}
@Override
public boolean hasNext()
{
return lhsIter.hasNext() || rhsIter.hasNext();
}
@Override
public RetType next()
{
if (!hasNext()) {
throw new NoSuchElementException();
}
return binaryFn.apply(
lhsIter.hasNext() ? lhsIter.next() : null,
rhsIter.hasNext() ? rhsIter.next() : null
);
}
@Override
public void remove()
{
throw new UnsupportedOperationException();
}
}