Java example source code file (VersionTest.java)

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Java - Java tags/keywords

class, ecma, edition, exception, expected, javascript, js_lang_version, runtimeexception, scriptenginemanager, string, unknown, versiontest

The VersionTest.java Java example source code

/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 6346729 6705893
 * @summary Create JavaScript engine and check language and engine version
 */

import javax.script.*;
import java.io.*;

public class VersionTest  {
        private static final String JS_LANG_VERSION = "ECMA - 262 Edition 5.1";

        public static void main(String[] args) throws Exception {
            ScriptEngineManager manager = new ScriptEngineManager();
            ScriptEngine jsengine = Helper.getJsEngine(manager);
            if (jsengine == null) {
                System.out.println("Warning: No js engine found; test vacuously passes.");
                return;
            }
            String langVersion = jsengine.getFactory().getLanguageVersion();
            if (! langVersion.equals(JS_LANG_VERSION)) {
                throw new RuntimeException("Expected JavaScript version is " +
                            JS_LANG_VERSION);
            }
            String engineVersion = jsengine.getFactory().getEngineVersion();
            String expectedVersion = getNashornVersion();
            if (! engineVersion.equals(expectedVersion)) {
                throw new RuntimeException("Expected version is " + expectedVersion);
            }
        }

        private static String getNashornVersion() {
            try {
                Class versionClass = Class.forName("jdk.nashorn.internal.runtime.Version");
                return (String) versionClass.getMethod("version").invoke(null);
            } catch (Exception e) {
                return "Version Unknown!";
            }
        }
}