Benchmark using Optional/Streams vs. imperative variants of the same code

Benchmarks.java

/*
 * Copyright 2019 the original author or authors.
 *
 * 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 benchmarks;

import java.util.concurrent.TimeUnit;

import org.junit.platform.commons.annotation.Testable;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;

/**
 * @author Mark Paluch
 */
@Warmup(iterations = 3, time = 2)
@Measurement(iterations = 3, time = 2)
@Fork(value = 1)
@State(Scope.Thread)
@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.SECONDS)
@Testable
public class Benchmarks {

	private final Source imperative = new ImperativeSource();

	private final Source stream = new StreamSource();

	@Benchmark
	public Object getOptionalImperative() {
		return imperative.getItem("thr").orElse("not found");
	}

	@Benchmark
	public Object getOptionalStream() {
		return stream.getItem("thr").orElse("not found");
	}

	@Benchmark
	public Object getNullableImperative() {

		String result = imperative.getNullableItem("thr");

		return result == null ? "not found" : result;
	}

	@Benchmark
	public Object getNullableStream() {

		String result = stream.getNullableItem("thr");

		return result == null ? "not found" : result;
	}
}

ImperativeSource.java

/*
 * Copyright 2019 the original author or authors.
 *
 * 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 benchmarks;import java.util.Arrays;
import java.util.List;
import java.util.Optional;

/**
 * @author Mark Paluch
 */
public class ImperativeSource implements Source {

	private final List<MyItem> items = Arrays
			.asList(new MyItem("one"), new MyItem("two"), new MyItem("three"));

	@Override
	public Optional<String> getItem(String filter) {
		return Optional.ofNullable(getNullableItem(filter));
	}

	@Override
	public String getNullableItem(String filter) {

		for (MyItem item : items) {
			if (item.getValue().startsWith(filter)) {
				return item.getValue();
			}
		}

		return null;
	}

	static class MyItem {
		private final String value;

		public MyItem(String value) {
			this.value = value;
		}

		public String getValue() {
			return this.value;
		}
	}
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>stream-optional-jmh</groupId>
	<artifactId>stream-optional-jmh</artifactId>
	<version>1.0-SNAPSHOT</version>


	<properties>
		<maven.compiler.source>1.8</maven.compiler.source>
		<maven.compiler.target>1.8</maven.compiler.target>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.openjdk.jmh</groupId>
			<artifactId>jmh-core</artifactId>
			<version>1.21</version>
		</dependency>

		<dependency>
			<groupId>org.openjdk.jmh</groupId>
			<artifactId>jmh-generator-annprocess</artifactId>
			<version>1.21</version>
		</dependency>

		<dependency>
			<groupId>com.github.mp911de.microbenchmark-runner</groupId>
			<artifactId>microbenchmark-runner-junit5</artifactId>
			<version>0.1.0.RELEASE</version>
		</dependency>

	</dependencies>

	<repositories>
		<repository>
			<id>jitpack.io</id>
			<url>https://jitpack.io</url>
		</repository>
	</repositories>

</project>

results.txt

Java 8:

Benchmarks.getNullableImperative  thrpt    3  100776671,872 ± 83086492,635  ops/s
Benchmarks.getNullableStream      thrpt    3   15769775,360 ±  2679082,192  ops/s
Benchmarks.getOptionalImperative  thrpt    3  103626247,773 ± 13883128,975  ops/s
Benchmarks.getOptionalStream      thrpt    3   16060717,979 ±  4156670,804  ops/s

Source.java

/*
 * Copyright 2019 the original author or authors.
 *
 * 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 benchmarks;import java.util.Arrays;
import java.util.List;
import java.util.Optional;

/**
 * @author Mark Paluch
 */
public interface Source {

	Optional<String> getItem(String filter);

	String getNullableItem(String filter);
}

StreamSource.java

/*
 * Copyright 2019 the original author or authors.
 *
 * 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 benchmarks;import java.util.Arrays;
import java.util.List;
import java.util.Optional;

/**
 * @author Mark Paluch
 */
public class StreamSource implements Source {

	private final List<MyItem> items = Arrays
			.asList(new MyItem("one"), new MyItem("two"), new MyItem("three"));

	@Override
	public Optional<String> getItem(String filter) {
		return items.stream().map(MyItem::getValue).filter(it -> it.startsWith(filter))
				.findFirst();
	}

	@Override
	public String getNullableItem(String filter) {
		return getItem(filter).orElse(null);
	}

	static class MyItem {
		private final String value;

		public MyItem(String value) {
			this.value = value;
		}

		public String getValue() {
			return this.value;
		}
	}
}

CPU Profile

Memory Profile