Which Java Version Detection - JavaScript Utilities

When developers ask "which Java version should I use" in JavaScript contexts, they usually need version detection utilities. These code snippets help you programmatically determine versions and make informed decisions about which technology stack to use.

Node.js Version Detection Utilities #

Basic Version Check #

Version Comparison Utility #

Environment Detection Utilities #

JavaScript Runtime Detection #

Java Version Detection (When Needed) #

Check Java Availability #

// Node.js utility to check if Java is installed
const { exec } = require('child_process');

function checkJavaVersion(callback) {
  exec('java -version', (error, stdout, stderr) => {
    if (error) {
      callback({ installed: false, error: 'Java not found' });
      return;
    }
    
    // Java outputs version to stderr
    const versionOutput = stderr;
    const versionMatch = versionOutput.match(/version "(.+?)"/);
    
    if (versionMatch) {
      const version = versionMatch[1];
      callback({
        installed: true,
        version: version,
        isLTS: version.includes('17.') || version.includes('21.'),
        output: versionOutput
      });
    } else {
      callback({ installed: false, error: 'Could not parse version' });
    }
  });
}

// Usage example (Node.js only)
// checkJavaVersion((result) => {
//   console.log('Java status:', result);
// });

Project Technology Stack Detection #

Detect Project Type #

Version Recommendation Engine #

Smart Version Selector #

Quick Reference Utility #

All-in-One Version Checker #

Summary #

These utilities help you programmatically answer "which Java version should I use" by:

• Detecting Node.js versions and comparing against requirements
• Identifying project types to determine if you need Java or JavaScript
• Providing smart recommendations based on your development context
• Checking Java availability when actually needed

Most JavaScript developers need Node.js LTS versions (18.x or 20.x), not Java. Use these snippets to make informed decisions about your development environment.