Object-to-object mapping framework microbenchmark

Multi-layered applications often require to map between different object models (e.g. DTOs and entities).
Writing such boiler plate mapping code is a tedious and error-prone task.
A lot of object-to-object mapping Java frameworks aims to simplify this work and automate it.
Some uses code instrospection (eg. Dozer). Other uses code generation (ex: MapStruct).
This micro-benchmark compares performance of 9 frameworks. Results could be compared to the benchmark of a code written manually.

Benchmark are powered by a tool called JMH or also known as "Java Microbenchmarking Harness".
JMH is developed by the OpenJDK team.

Benchmarked object to object mapper frameworks

• Dozer
• MapStruct
• ModelMapper
• Selma
• Orika
• JMapper
• BULL
• datus
• ReMap
• SJF4J

Contributing to benchmark

Github is for social coding platform: if you want to add another mapping framework or optimize an existing one, we
encourage contributions
through pull requests from forks of this repository.
If you want to contribute code this way, please reference a GitHub ticket as well covering the specific issue you are
addressing.
To add a new mapper, please add a unit test that extends the AbstractMapperTest class and declare your mapper into the
MapperBenchmark class.

Data model

The data model used by this benchmark is very basic. It comes from the Comparison class from the ModelMapper framework.
It includes combinations which usually appear in Java Beans, such as:

• Object types
• Collections

Launch the benchmark

Pre-requisites: Maven 3.x and a JDK 17 (or above)

git clone git://github.com/arey/java-object-mapper-benchmark.git

mvn clean install

java @jvm.options -jar target/benchmarks.jar

Optional: To run a single benchmark, such as MapStruct, use
java @jvm.options -jar target/benchmarks.jar -p type=MapStruct

Interpreting the Results

The benchmarks measure throughput, given in "ops/time". The time unit used is seconds.
Generally, the score represents the number of graph object mapped per second; the higher the score, the better.

Results

Tests has been performed on:

• OS: macOS Tahoe 26.5
• CPU: Apple M4 Pro
• RAM: 24 GB
• JVM: Eclipse Temurin 21.0.5+11

Benchmark	Mode	Samples	Score	Score Error (99,9%)	Units
Manual	thrpt	200	98 433 829	560 874	ops/s
SJF4J	thrpt	200	96 845 484	1 137 711	ops/s
MapStruct	thrpt	200	94 501 314	1 153 765	ops/s
Selma	thrpt	200	92 624 594	1 032 208	ops/s
JMapper	thrpt	200	83 623 847	404 936	ops/s
datus	thrpt	200	33 690 856	863 388	ops/s
Orika	thrpt	200	15 488 089	385 665	ops/s
ReMap	thrpt	200	2 020 680	127 259	ops/s
ModelMapper	thrpt	200	451 548	7 450	ops/s
BULL	thrpt	200	387 895	6 636	ops/s
Dozer	thrpt	200	333 334	10 383	ops/s

Documentation

• Micro-benchmark of Java mapping object frameworks (french article)

Generating plot

1. Run benchmark while exporting results to csv with java @jvm.options -jar target/benchmarks.jar -rff results.csv -rf csv
2. Use gnuplot to generate plot with gnuplot benchmark.plt. This will output results.png.

Credits

• Uses Maven as a build tool
• Uses JMH for Java Microbenchmarking Harness