Command line utility to find JVM versions on macOS and Linux (Debian, Ubuntu, RHEL/CentOS & Fedora) - useful for setting JAVAHOME_, particularly on machines with different JVM versions and architectures.
I'm thinking of you, Java Devs with Apple Silicon hardware 🐱💻
The utility can be installed using Homebrew via the homebrew-javalocate tap:
bash
brew tap dameikle/javalocate
brew install javalocate
Or using Cargo via the javalocate crate on crates.io:
bash
cargo install javalocate
The utility is designed to be used in a similar fashion to the /usr/libexec/javahome_ by providing a number of flags that can be passed to control the selection.
These are shown below:
OPTIONS:
-a, --arch <ARCH> Architecture to filter on (e.g. x86_64, aarch64, amd64)
-d, --detailed Print out full details
-f, --fail Return error code if no JVM found
-h, --help Print help information
-n, --name <NAME> JVM Name to filter on
-v, --version <VERSION> Version to filter on (e.g. 1.8, 11, 17, etc)
By default, the utility outputs a single path location to the "top" JVM found, ordered by descending version (i.e. Java 17 > Java 8), prioritising the system architecture (i.e. aarch64 > x86_64 on a Apple Silicon Mac).
Passing the detailed flag (--detailed or -d) prints the full details of all JVMs found.
This flag can also be used in conjunction with filters to display full details for the filtered set.
The filtering options of name, version and arch can be used in isolation or together to fine tune the selection.
For example, to get the path to Java 17
bash
javalocate -v 17
Or to get the path to the x86_64 JVM for Java 11
bash
javalocate -v 11 -a x86_64
Or to get the path to latest aarch64 JVM available
bash
javalocate -a aarch64
You can also specify a minimum version by appending a + to the version:
bash
javalocate -v 1.8+
By default, the utility returns an OK (0) exit code whether a JVM is found or not.
Setting the fail flag (--fail or _-f) changes this behaviour, returning a CONFIG ERROR (78) exit code.
This can be useful if you want to use the utility in a shell script.
For example, the below would return an error code if Java 11 or above could not be found when trying to set the JAVAHOME_ environment variable:
bash
export JAVA_HOME=$(javalocate -v 11+ -f)
The utility looks in the default JVM installation locations for the following operating systems:
| Operating System | Location | |------------------|-----------------------------------| | macOS | /Library/Java/JavaVirtualMachines | | Ubuntu | /usr/lib/jvm | | Debian | /usr/lib/jvm | | RHEL | /usr/lib/jvm | | CentOS | /usr/lib/jvm | | Fedora | /usr/lib/jvm |
It assumes that the release file is included in the JVM package on Linux, and the release file and Info.plist file is packaged on macOS.
Experimental support has been added to build information from path file name where release file is not available. This can occur on older JVMs.
Adding the following to your ~/.bashrc (or ~/.bashaliases_) file:
bash
setjava() {
export JAVA_HOME=`javalocate -v $1`
}
Allows you to quickly flip between versions:
bash
setjava 17
echo $JAVA_HOME
setjava 8
echo $JAVA_HOME
setjava 11
echo $JAVA_HOME
The utility is developed in Rust and can be build from source using:
cargo build
Or for a release version
cargo build --profile release
Copyright 2022 David Meikle
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.