Running Java in Node.js

Node.js is an event-driven JavaScript runtime platform that is built using the Chrome’s V8 JavaScript engine. Node is mainly used for building large-scale applications. In this article, we will see how to run a Java code in Node.js.

Steps

• Check if Node.js is already installed on your system using the following command −

npm init

• Install Java on your local system as npm package

npm install java

Ensure that Java is already installed on your system. If not, you need to install Java on your system before running the following code.

Example 1

Create a file with the name "runJava.js" and copy the following code snippet. After creating the file, use the command "node runJava.js" to run this code.

// Importing the Java module
var java = require('java');
var javaLangSystem = java.import('java.lang.System');

// Printing statement using Java in node
javaLangSystem.out.printlnSync('I Love Tutorials Point <3');

Output

C:\home\node>> node runJava.js
1.false
2.true
3.false

Example 2

Let’s have a look at one more example

// Importing the Java module
var java = require('java');
var javaLangSystem = java.import('java.lang.System');

// Defining variables
var a = 10;
var b = 20

// Printing statement using Java in node
javaLangSystem.out.printlnSync(a + ' + ' + b + " = " + (a+b));

Output

C:\home\node>> node runJava.js
10 + 20 = 30