ca.uhn.fhir.util.TaskChunker Maven / Gradle / Ivy
package ca.uhn.fhir.util;
/*-
* #%L
* HAPI FHIR - Core Library
* %%
* Copyright (C) 2014 - 2024 Smile CDR, 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.
* #L%
*/
import com.google.common.collect.Streams;
import jakarta.annotation.Nonnull;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.function.Consumer;
import java.util.stream.Stream;
/**
* This utility takes an input collection, breaks it up into chunks of a
* given maximum chunk size, and then passes those chunks to a consumer for
* processing. Use this to break up large tasks into smaller tasks.
*
* @since 6.6.0
* @param The type for the chunks
*/
public class TaskChunker {
public void chunk(Collection theInput, int theChunkSize, Consumer> theBatchConsumer) {
List input;
if (theInput instanceof List) {
input = (List) theInput;
} else {
input = new ArrayList<>(theInput);
}
for (int i = 0; i < input.size(); i += theChunkSize) {
int to = i + theChunkSize;
to = Math.min(to, input.size());
List batch = input.subList(i, to);
theBatchConsumer.accept(batch);
}
}
@Nonnull
public Stream> chunk(Stream theStream, int theChunkSize) {
return StreamUtil.partition(theStream, theChunkSize);
}
@Nonnull
public void chunk(Iterator theIterator, int theChunkSize, Consumer> theListConsumer) {
chunk(Streams.stream(theIterator), theChunkSize).forEach(theListConsumer);
}
}