JVenv

This project unites the efforts to combine https://github.com/jenv/jenv and https://github.com/FelixSelter/JEnv-for-Windows/ to a cross platform solution. The readme of this project which is in a very early stage of development should temporarily function as a design document. Please contribute by expanding it or implementing ideas from it. Everything in this document is temporary and may be changed by you. Once sections of this document grow to large they will be moved into the wiki submodule.

The main problem creating an application like JEnv is that changing the environment variables of the current shell session can only be done by a script of that specific shell. Therefore development of these tools lead naturally to no cross platform solution.

The idea of this tool is to have a main codebase that handles common tasks as jdk installation, discovery and keeping track of the global java version. Additionally there will be a collection of small shell specific scripts that query the main cross platform code and change the necessary environment variables. These script should be kept as minimal as possible. Creating as many scripts for all the different shells out there is a key feature. Please expand the list of shells that need to be supported below.

The repository currently contains very basic rust code that allows for a cross platform config file and type safe command line argument parsing. The language for this tool is still up to debate. Basic requirements for a language to write this tool in are static type safety, cross platform support and that it does not require an additional runtime to be installed (e.g. Python)

List of supported shells

List of shells that need to be supported

• bash
• powershell
• fish
• cmd

List of cli commands and their function

java-home

• Returns the java home for a specific directory so the shell script can update the environment variables when it is activated

auto-scan

• Tries to find installed jvms on the system to add them to the config file

list

• lists all the jvms with their alias name from the config. Shows the current active global version, shell version and local version

install

• install a specific jdk (disco api?)
• sdkman support?

uninstall

• uninstall a specific jdk

integrate

• automatically configure a shell to work with the jvenv script

global

• Change the global java version

use

• Change the java version of the current shell

init

• Create a project by creating a .java-version file with the given java version

register

• Add a jdk to the config and create an alias

unregister

• Remove a jdk from the config

uninstall-jvenv

restore

• Load a backup of the environment variables

rename

• rename a java installation

Shell scripts

Every shell needs a way to reload its environment variables after the jvenv script has been executed. Shells should also reload on directory change and open

Other

The config needs to be validated after loading. Check if all java installations still exist etc.