njar

njar

Running JAR files on node.js

This package helps with running JAR files or Java classes on Node.js.

Preview

Example

For more details, see the example.

Install

npm install njar --save # install locally
npm install njar -g # or install globally

Usage

Install a specify version of openJDK

njar install 16 # install openjdk16
njar use 16 # use openjdk16

Running JAR files on CLI

# running jar files
njar exec ./Math.jar add 11 22

# running jar files with cp
njar exec -cp ./Math.jar App.Main add 11 22
# running compiled classes with cp
njar exec -cp . App.Main add 11 22

Running JAR files programmatically

const path = require('path')
const { execute } = require('njar')

async function main() {
  const jarPath = path.join(__dirname, './Math.jar')
  const result = await execute(jarPath, ['add', '2', '4'])
  console.log(result) // '6'
}

main()

Running with cp

const path = require('path')
const { executeWithCP } = require('njar')

async function main() {
  const className = 'App.Main'
  const classPaths = path.join(__dirname, '.')
  const result = await executeWithCP(classPaths, className, [
    'multiply',
    '2',
    '3',
  ])
  console.log(result) // '6'
}

main()

All CLI commands

njar install [version]  # Install a JDK version
njar use [version]      # Set the JDK version
njar versions           # List all JDK versions available to njar
njar which              # Display the full path to an executable
njar exec               # Running java application
njar --help             # Show help information