Programming language: Java
Tags: Projects     Introspection    
Latest version: v3.1

Objenesis alternatives and similar libraries

Based on the "Introspection" category

  • Reflections

    Reflections scans your classpath, indexes the metadata, allows you to query it on runtime and may save and collect that information for many modules within your project.
  • jOOR

    jOOR stands for jOOR Object Oriented Reflection. It is a simple wrapper for the java.lang.reflect package.
  • ClassGraph

    ClassGraph (formerly FastClasspathScanner) is an uber-fast, ultra-lightweight, parallelized classpath scanner and module scanner for Java, Scala, Kotlin and other JVM languages.
  • ReflectASM

    ReflectASM is a very small Java library that provides high performance reflection by using code generation.
  • Mirror

    Mirror was created to bring light to a simple problem, usually named ReflectionUtil, which is on almost all projects that rely on reflection to do advanced tasks.

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Objenesis is a library dedicated to bypass the constructor when creating an object. On any JVM there is.

You can find the website and user documentation at objenesis.org.

Developer information

Project status

Build Status Maven Central

Environment setup

I'm using:

  • Maven 3.6.2
  • IntelliJ Ultimate 2019.3 (thanks to JetBrains for the license) (it should also work with Eclipse)

To configure your local workspace:

  • Import the Maven parent project to Eclipse or IntelliJ
  • Import the Eclipse formatting file objenesis-formatting.xml (usable in Eclipse or IntelliJ)

To build with Maven

There are two different levels of build.

Build without any active profile

It is a basic compilation of the application.

mvn install

Full build

This build will create the source and javadoc jars and run spotbugs.

mvn install -Pfull

To run special builds

Run the Android TCK

  • Install the Android SDK (brew cask install android-sdk)
  • Install platform-tools and build-tools using the sdkmanager (sdkmanager "platform-tools" "build-tools")
  • Add an ANDROID_HOME to target the Android SDK (export ANDROID_HOME=$(realpath $(echo "$(dirname $(readlink $(which sdkmanager)))/../..")))
  • Configure a device (real or simulated) and launch it
  • Activate the debug mode if it's a real device
  • mvn package -Pandroid

Run the benchmarks

mvn package -Pbenchmark
cd benchmark

Generate the website

mvn package -Pwebsite

To update the versions

  • mvn versions:set -DnewVersion=X.Y -Pall
  • mvn versions:commit -Pall if everything is ok, mvn versions:revert -Pall otherwise

Configure to deploy to the Sonatype maven repository

  • You will first need to add something like this to your settings.xml xml <servers> <server> <id>sonatype-nexus-snapshots</id> <username>sonatypeuser</username> <password>sonatypepassword</password> </server> <server> <id>sonatype-nexus-staging</id> <username>sonatypeuser</username> <password>sonatypepassword</password> </server> </servers>
  • Then follow the instructions from the site below to create your key to sign the deployed items


To check dependencies and plugins versions

mvn versions:display-dependency-updates versions:display-plugin-updates -Pall

To upgrade the Maven wrapper

mvn -N io.takari:maven:wrapper -Dmaven=3.6.2

To update the license

mvn validate license:format -Pall

To release

  • Add the release notes in website/site/content/notes.html You use this code to generate it
# Get the milestone matching the version
milestone=$(curl -s "https://api.github.com/repos/easymock/objenesis/milestones" | jq ".[] | select(.title==\"$version\") | .number")
echo "<h1>Version $version ($(date '+%Y-%m-%d'))</h1>"
echo "<ul>"  
curl -s "https://api.github.com/repos/easymock/objenesis/issues?milestone=${milestone}&state=all" | jq -r '.[] | "  <li>" + .title + " (#" + (.number|tostring) + ")</li>"'
echo "</ul>"
  • Add these servers to your settings.xml
  • Set gpg_passphrase, bintray_api_key and bintray_user environment variables
  • Launch an Android device (virtual or physical)
  • Launch ./deploy.sh version
  • Answer the questions (normally, just acknowledge the proposed default)
  • Follow the instructions

If something fails and you need to rollback a bit, the following commands might help:

mvn release:rollback -Pall
git tag -d $version
git push origin :refs/tags/$version
git reset --hard HEAD~2

Deploy the website

  • Make sure the pom is at the version you want to release
  • Launch ./deploy-website.sh

*Note that all licence references and agreements mentioned in the Objenesis README section above are relevant to that project's source code only.