ClosureCompiler.js

1.6.1 verified Fri May 01 auth: no javascript deprecated

A Node.js wrapper for Google Closure Compiler that automatically downloads and sets up a JRE (from OpenJDK) and the compiler JAR. Version 1.6.1 (circa 2015) is the last stable release. This project is **deprecated** and no longer maintained; users should migrate to google-closure-compiler or google-closure-compiler-js. Key differentiator: self-contained (bundles JRE), but outdated compared to official or Java-free alternatives.

Common errors

error Error: Could not find any Java installation ↓

cause No JRE/JDK installed and automatic download failed

fix

Install Java or ensure JAVA_HOME is set

error FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed ↓

cause Out of memory during compilation of large codebase

fix

Increase JVM heap via options: -xmx2048m

error Error: spawn ENOENT ↓

cause ccjs command not found or Java not available

fix

Install globally with -g or check Java installation

Warnings

deprecated This package is deprecated. Alternatives: google-closure-compiler, google-closure-compiler-js ↓

fix Migrate to google-closure-compiler or google-closure-compiler-js

gotcha Requires Java runtime; if JRE not found, package may download a bundled OpenJDK ~45MB ↓

fix Install Java beforehand to avoid the download

gotcha Options are case-insensitive in the API but must be snake_case (not camelCase) ↓

fix Use compilation_level instead of compilationLevel

gotcha The --js_output_file flag is NOT supported; use shell redirection ↓

fix Redirect stdout to file: ccjs files > output.js

Install

npm install closurecompiler

yarn add closurecompiler

pnpm add closurecompiler

Imports

compile

wrong

import ClosureCompiler from 'closurecompiler'

correct

var ClosureCompiler = require('closurecompiler');

CJS only; no default ESM export.

ClosureCompiler.compile

wrong

ClosureCompiler.compile(files, callback, options)

correct

ClosureCompiler.compile(files, options, callback)

Second argument must be options object, not callback.

ccjs CLI

wrong

ccjs sourceFiles... --js_output_file output.js

correct

ccjs sourceFiles... [options] > output.js

Use shell redirection for output; --js_output_file is not supported.

Quickstart

Demonstrates basic usage: compile a JavaScript file with advanced optimizations and Node.js externs.

var ClosureCompiler = require('closurecompiler');
ClosureCompiler.compile(['input.js'], {
    compilation_level: 'ADVANCED_OPTIMIZATIONS',
    warning_level: 'VERBOSE',
    externs: ['node']
}, function(err, result) {
    if (err) console.error(err);
    else console.log(result);
});