/*
* Copyright (c) 2010, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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
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*/
package jdk.nashorn.api.scripting;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineFactory;
import jdk.nashorn.internal.runtime.Context;
import jdk.nashorn.internal.runtime.Version;
/**
* JSR-223 compliant script engine factory for Nashorn. The engine answers for:
* <ul>
* <li>names {@code "nashorn"}, {@code "Nashorn"}, {@code "js"}, {@code "JS"}, {@code "JavaScript"},
* {@code "javascript"}, {@code "ECMAScript"}, and {@code "ecmascript"};</li>
* <li>MIME types {@code "application/javascript"}, {@code "application/ecmascript"}, {@code "text/javascript"}, and
* {@code "text/ecmascript"};</li>
* <li>as well as for the extension {@code "js"}.</li>
* </ul>
* Programs executing in engines created using {@link #getScriptEngine(String[])} will have the passed arguments
* accessible as a global variable named {@code "arguments"}.
*
* @since 1.8u40
*/
public final class NashornScriptEngineFactory implements ScriptEngineFactory {
@Override
public String getEngineName() {
return (String) getParameter(ScriptEngine.ENGINE);
}
@Override
public String getEngineVersion() {
return (String) getParameter(ScriptEngine.ENGINE_VERSION);
}
@Override
public List<String> getExtensions() {
return Collections.unmodifiableList(extensions);
}
@Override
public String getLanguageName() {
return (String) getParameter(ScriptEngine.LANGUAGE);
}
@Override
public String getLanguageVersion() {
return (String) getParameter(ScriptEngine.LANGUAGE_VERSION);
}
@Override
public String getMethodCallSyntax(final String obj, final String method, final String... args) {
final StringBuilder sb = new StringBuilder().append(obj).append('.').append(method).append('(');
final int len = args.length;
if (len > 0) {
sb.append(args[0]);
}
for (int i = 1; i < len; i++) {
sb.append(',').append(args[i]);
}
sb.append(')');
return sb.toString();
}
@Override
public List<String> getMimeTypes() {
return Collections.unmodifiableList(mimeTypes);
}
@Override
public List<String> getNames() {
return Collections.unmodifiableList(names);
}
@Override
public String getOutputStatement(final String toDisplay) {
return "print(" + toDisplay + ")";
}
@Override
public Object getParameter(final String key) {
switch (key) {
case ScriptEngine.NAME:
return "javascript";
case ScriptEngine.ENGINE:
return "Oracle Nashorn";
case ScriptEngine.ENGINE_VERSION:
return Version.version();
case ScriptEngine.LANGUAGE:
return "ECMAScript";
case ScriptEngine.LANGUAGE_VERSION:
return "ECMA - 262 Edition 5.1";
case "THREADING":
// The engine implementation is not thread-safe. Can't be
// used to execute scripts concurrently on multiple threads.
return null;
default:
return null;
}
}
@Override
public String getProgram(final String... statements) {
Objects.requireNonNull(statements);
final StringBuilder sb = new StringBuilder();
for (final String statement : statements) {
sb.append(Objects.requireNonNull(statement)).append(';');
}
return sb.toString();
}
// default options passed to Nashorn script engine
private static final String[] DEFAULT_OPTIONS = new String[] { "-doe" };
@Override
public ScriptEngine getScriptEngine() {
try {
return new NashornScriptEngine(this, DEFAULT_OPTIONS, getAppClassLoader(), null);
} catch (final RuntimeException e) {
if (Context.DEBUG) {
e.printStackTrace();
}
throw e;
}
}
/**
* Create a new Script engine initialized with the given class loader.
*
* @param appLoader class loader to be used as script "app" class loader.
* @return newly created script engine.
* @throws SecurityException
* if the security manager's {@code checkPermission}
* denies {@code RuntimePermission("nashorn.setConfig")}
*/
public ScriptEngine getScriptEngine(final ClassLoader appLoader) {
return newEngine(DEFAULT_OPTIONS, appLoader, null);
}
/**
* Create a new Script engine initialized with the given class filter.
*
* @param classFilter class filter to use.
* @return newly created script engine.
* @throws NullPointerException if {@code classFilter} is {@code null}
* @throws SecurityException
* if the security manager's {@code checkPermission}
* denies {@code RuntimePermission("nashorn.setConfig")}
*/
public ScriptEngine getScriptEngine(final ClassFilter classFilter) {
return newEngine(DEFAULT_OPTIONS, getAppClassLoader(), Objects.requireNonNull(classFilter));
}
/**
* Create a new Script engine initialized with the given arguments.
*
* @param args arguments array passed to script engine.
* @return newly created script engine.
* @throws NullPointerException if {@code args} is {@code null}
* @throws SecurityException
* if the security manager's {@code checkPermission}
* denies {@code RuntimePermission("nashorn.setConfig")}
*/
public ScriptEngine getScriptEngine(final String... args) {
return newEngine(Objects.requireNonNull(args), getAppClassLoader(), null);
}
/**
* Create a new Script engine initialized with the given arguments and the given class loader.
*
* @param args arguments array passed to script engine.
* @param appLoader class loader to be used as script "app" class loader.
* @return newly created script engine.
* @throws NullPointerException if {@code args} is {@code null}
* @throws SecurityException
* if the security manager's {@code checkPermission}
* denies {@code RuntimePermission("nashorn.setConfig")}
*/
public ScriptEngine getScriptEngine(final String[] args, final ClassLoader appLoader) {
return newEngine(Objects.requireNonNull(args), appLoader, null);
}
/**
* Create a new Script engine initialized with the given arguments, class loader and class filter.
*
* @param args arguments array passed to script engine.
* @param appLoader class loader to be used as script "app" class loader.
* @param classFilter class filter to use.
* @return newly created script engine.
* @throws NullPointerException if {@code args} or {@code classFilter} is {@code null}
* @throws SecurityException
* if the security manager's {@code checkPermission}
* denies {@code RuntimePermission("nashorn.setConfig")}
*/
public ScriptEngine getScriptEngine(final String[] args, final ClassLoader appLoader, final ClassFilter classFilter) {
return newEngine(Objects.requireNonNull(args), appLoader, Objects.requireNonNull(classFilter));
}
private ScriptEngine newEngine(final String[] args, final ClassLoader appLoader, final ClassFilter classFilter) {
checkConfigPermission();
try {
return new NashornScriptEngine(this, args, appLoader, classFilter);
} catch (final RuntimeException e) {
if (Context.DEBUG) {
e.printStackTrace();
}
throw e;
}
}
// -- Internals only below this point
private static void checkConfigPermission() {
final SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(new RuntimePermission(Context.NASHORN_SET_CONFIG));
}
}
private static final List<String> names;
private static final List<String> mimeTypes;
private static final List<String> extensions;
static {
names = immutableList(
"nashorn", "Nashorn",
"js", "JS",
"JavaScript", "javascript",
"ECMAScript", "ecmascript"
);
mimeTypes = immutableList(
"application/javascript",
"application/ecmascript",
"text/javascript",
"text/ecmascript"
);
extensions = immutableList("js");
}
private static List<String> immutableList(final String... elements) {
return Collections.unmodifiableList(Arrays.asList(elements));
}
private static ClassLoader getAppClassLoader() {
// Revisit: script engine implementation needs the capability to
// find the class loader of the context in which the script engine
// is running so that classes will be found and loaded properly
final ClassLoader ccl = Thread.currentThread().getContextClassLoader();
return (ccl == null)? NashornScriptEngineFactory.class.getClassLoader() : ccl;
}
}