| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.hudi.client.utils; |
| |
| import java.util.Iterator; |
| import java.util.function.Function; |
| import org.apache.avro.generic.GenericRecord; |
| |
| import org.apache.hudi.common.util.ValidationUtils; |
| import org.apache.hudi.common.util.collection.Pair; |
| |
| public class MergingIterator<T extends GenericRecord> implements Iterator<T> { |
| |
| private final Iterator<T> leftIterator; |
| private final Iterator<T> rightIterator; |
| private final Function<Pair<T,T>, T> mergeFunction; |
| |
| public MergingIterator(Iterator<T> leftIterator, Iterator<T> rightIterator, Function<Pair<T,T>, T> mergeFunction) { |
| this.leftIterator = leftIterator; |
| this.rightIterator = rightIterator; |
| this.mergeFunction = mergeFunction; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| boolean leftHasNext = leftIterator.hasNext(); |
| boolean rightHasNext = rightIterator.hasNext(); |
| ValidationUtils.checkArgument(leftHasNext == rightHasNext); |
| return leftHasNext; |
| } |
| |
| @Override |
| public T next() { |
| return mergeFunction.apply(Pair.of(leftIterator.next(), rightIterator.next())); |
| } |
| } |