org.apache.flink.runtime.util.RegularToMutableObjectIterator Maven / Gradle / Ivy
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* 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.flink.runtime.util;
import java.util.Iterator;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.util.MutableObjectIterator;
public class RegularToMutableObjectIterator implements MutableObjectIterator {
private final Iterator iterator;
private final TypeSerializer serializer;
public RegularToMutableObjectIterator(Iterator iterator, TypeSerializer serializer) {
this.iterator = iterator;
this.serializer = serializer;
}
@Override
public T next(T reuse) {
// -----------------------------------------------------------------------------------------
// IMPORTANT: WE NEED TO COPY INTO THE REUSE OBJECT TO SIMULATE THE MUTABLE OBJECT RUNTIME
// -----------------------------------------------------------------------------------------
if (this.iterator.hasNext()) {
return this.serializer.copy(this.iterator.next(), reuse);
} else {
return null;
}
}
@Override
public T next() {
if (this.iterator.hasNext()) {
return this.iterator.next();
} else {
return null;
}
}
}