A Java version manager heavily inspired by
rbenv and
tfenv. javaenv manages your installed
Java versions and allows for keeping the Java version for a project under
version control.
jEnv is a great tool with similar goals. However, I wanted javaenv to manage the full life cycle of the Java environment, including installation, in order to simplify some workflows.
javaenv supports Linux and Mac OS X. Support for Windows should be doable but is not on my roadmap.
git clone https://github.com/protocol7/javaenv.git ~/.javaenv
javaenv is a self-contained script and requires Python 3.3 or newer to run.
For convenience, add javaenv to your $PATH, e.g. using:
ln -s ~/.javaenv/javaenv /usr/local/bin
Shim the Java command line tools:
ln -s ~/.javaenv/javaenv /usr/local/bin/java
ln -s ~/.javaenv/javaenv /usr/local/bin/javac
...
This will allow you to automatically switch version for java, javac and
other tools, for example:
$ cd my-java-project
$ cat .javaversion
openjdk-11.0.2
$ javac -version
javac 11.0.2
Versions, as provided as command line arguments or in .javaversion files are
in the format of <distribution>-<version>. Supported distributions are:
adoptopenjdkcorrettoopenjdkoracle
A valid version would be, for example, openjdk-11.0.2.
The version can for some commands and for .javaversion files exclude the
distribution, in which case openjdk is used as the default. Thus, a valid
version can also be, for example, 11.0.2.
If a version is not provided for a command, or when calling Java command line
utilities, the version will be read from a file called .javaversion in the
current directory. This file should contain only the version, as defined above,
for example:
echo 'openjdk-11.0.2' > .javaversion
It is recommended that .javaversion is kept under version control with your
source code. This allows contributors to easily install and use the correct
Java version.
Installs a version of the JDK. The version to install can either be provided to
the command, or read from a .javaversion file. if the version is already
installed, this is a no-op. Thus, when starting work on a project using javaenv
you can simply run to be all set up:
javaenv install
Uninstall a specific version. The version must include the distribution name.
List locally installed versions
List all versions available for installation.
Print the value for JAVA_HOME for the active version. The version can either
be provided to the command, or read from a .javaversion file. The command is
useful for tools using JAVA_HOME, e.g. Maven.
export JAVA_HOME=$(javaenv home)
When downloading installation files, javaenv will verify the expected SHA256/MD6
hash. Note that the expected hash is stored in the javaenv command itself,
so this requires you to trust your javaenv installation.
- Add support for automatically shimming Java command line tools
- Add all released and still available versions
- Add support for building Docker images
- Add direct support for setting Java version for Maven
- [Long term] Remove need for Python