using java (.jar) in node.js

// step 1 install java
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer
sudo npm install java --save

// step 2 using
var java = require("java");
var jarfile = "jarfileName.jar";
java.classpath.push(jarPath);
java.import('package name');


// Examples proguard retrace.jar load
var jarfile = "retrace.jar"; //Download -> https://sourceforge.net/projects/proguard/  
var jarPath = path.join(__dirname, '..', 'proguard', jarfile);
java.classpath.push(jarPath);
var retrace = java.import('proguard.retrace.ReTrace');

// use Examples function  
retrace.getRetracedResult("param 1","param 2")      // -> [Function: bound callStaticMethod]
retrace.getRetracedResultSync("param 1","param 2")  // -> [Function: bound callStaticMethodSync]