Source: ptolemy/actor/lib/jjs/modules/os/os.js

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/** A Nashorn operating system module that implements a subset of the
 *  Node os module.
 *
 *  @module os
 *  @author Christopher Broosk
 *  @version $$Id$$
 */

// Stop extra messages from jslint.  Note that there should be no
// space between the / and the * and global.
/*globals Java, exports, require */
/*jshint globalstrict: true*/
"use strict";

/** Get the hostname.
 *  @return The hostname
 */
exports.hostname = function () {
    var InetAddress = Java.type('java.net.InetAddress');
    try {
        var result = InetAddress.getLocalHost().getHostName();
        if (result.length() !== 0) {
            return result;
        }
    } catch (e) {}

    var System = Java.type('java.lang.System');
    host = System.getenv("HOSTNAME");
    if (host !== null) {
        return host;
    }
    var host = System.getenv("COMPUTERNAME");
    if (host !== null) {
        return host;
    }
    return null;
};