/*
* Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package com.sun.script.javascript;
import com.sun.script.util.*;
import javax.script.*;
import sun.org.mozilla.javascript.internal.*;
import java.lang.reflect.Method;
import java.io.*;
import java.util.*;
/**
* Implementation of <code>ScriptEngine</code> using the Mozilla Rhino
* interpreter.
*
* @author Mike Grogan
* @author A. Sundararajan
* @since 1.6
*/
public final class RhinoScriptEngine extends AbstractScriptEngine
implements Invocable, Compilable {
private static final boolean DEBUG = false;
/* Scope where standard JavaScript objects and our
* extensions to it are stored. Note that these are not
* user defined engine level global variables. These are
* variables have to be there on all compliant ECMAScript
* scopes. We put these standard objects in this top level.
*/
private RhinoTopLevel topLevel;
/* map used to store indexed properties in engine scope
* refer to comment on 'indexedProps' in ExternalScriptable.java.
*/
private Map<Object, Object> indexedProps;
private ScriptEngineFactory factory;
private InterfaceImplementor implementor;
static {
ContextFactory.initGlobal(new ContextFactory() {
protected Context makeContext() {
Context cx = super.makeContext();
cx.setClassShutter(RhinoClassShutter.getInstance());
cx.setWrapFactory(RhinoWrapFactory.getInstance());
return cx;
}
public boolean hasFeature(Context cx, int feature) {
// we do not support E4X (ECMAScript for XML)!
if (feature == Context.FEATURE_E4X) {
return false;
} else {
return super.hasFeature(cx, feature);
}
}
});
}
/**
* Creates a new instance of RhinoScriptEngine
*/
public RhinoScriptEngine() {
Context cx = enterContext();
try {
topLevel = new RhinoTopLevel(cx, this);
} finally {
cx.exit();
}
indexedProps = new HashMap<Object, Object>();
//construct object used to implement getInterface
implementor = new InterfaceImplementor(this) {
protected Object convertResult(Method method, Object res)
throws ScriptException {
Class desiredType = method.getReturnType();
if (desiredType == Void.TYPE) {
return null;
} else {
return Context.jsToJava(res, desiredType);
}
}
};
}
public Object eval(Reader reader, ScriptContext ctxt)
throws ScriptException {
Object ret;
Context cx = enterContext();
try {
Scriptable scope = getRuntimeScope(ctxt);
String filename = (String) get(ScriptEngine.FILENAME);
filename = filename == null ? "<Unknown source>" : filename;
ret = cx.evaluateReader(scope, reader, filename , 1, null);
} catch (RhinoException re) {
if (DEBUG) re.printStackTrace();
int line = (line = re.lineNumber()) == 0 ? -1 : line;
String msg;
if (re instanceof JavaScriptException) {
msg = String.valueOf(((JavaScriptException)re).getValue());
} else {
msg = re.toString();
}
ScriptException se = new ScriptException(msg, re.sourceName(), line);
se.initCause(re);
throw se;
} catch (IOException ee) {
throw new ScriptException(ee);
} finally {
cx.exit();
}
return unwrapReturnValue(ret);
}
public Object eval(String script, ScriptContext ctxt) throws ScriptException {
if (script == null) {
throw new NullPointerException("null script");
}
return eval(new StringReader(script) , ctxt);
}
public ScriptEngineFactory getFactory() {
if (factory != null) {
return factory;
} else {
return new RhinoScriptEngineFactory();
}
}
public Bindings createBindings() {
return new SimpleBindings();
}
//Invocable methods
public Object invokeFunction(String name, Object... args)
throws ScriptException, NoSuchMethodException {
return invoke(null, name, args);
}
public Object invokeMethod(Object thiz, String name, Object... args)
throws ScriptException, NoSuchMethodException {
if (thiz == null) {
throw new IllegalArgumentException("script object can not be null");
}
return invoke(thiz, name, args);
}
private Object invoke(Object thiz, String name, Object... args)
throws ScriptException, NoSuchMethodException {
Context cx = enterContext();
try {
if (name == null) {
throw new NullPointerException("method name is null");
}
if (thiz != null && !(thiz instanceof Scriptable)) {
thiz = cx.toObject(thiz, topLevel);
}
Scriptable engineScope = getRuntimeScope(context);
Scriptable localScope = (thiz != null)? (Scriptable) thiz :
engineScope;
Object obj = ScriptableObject.getProperty(localScope, name);
if (! (obj instanceof Function)) {
throw new NoSuchMethodException("no such method: " + name);
}
Function func = (Function) obj;
Scriptable scope = func.getParentScope();
if (scope == null) {
scope = engineScope;
}
Object result = func.call(cx, scope, localScope,
wrapArguments(args));
return unwrapReturnValue(result);
} catch (RhinoException re) {
if (DEBUG) re.printStackTrace();
int line = (line = re.lineNumber()) == 0 ? -1 : line;
throw new ScriptException(re.toString(), re.sourceName(), line);
} finally {
cx.exit();
}
}
public <T> T getInterface(Class<T> clasz) {
try {
return implementor.getInterface(null, clasz);
} catch (ScriptException e) {
return null;
}
}
public <T> T getInterface(Object thiz, Class<T> clasz) {
if (thiz == null) {
throw new IllegalArgumentException("script object can not be null");
}
try {
return implementor.getInterface(thiz, clasz);
} catch (ScriptException e) {
return null;
}
}
private static final String printSource =
"function print(str, newline) { \n" +
" if (typeof(str) == 'undefined') { \n" +
" str = 'undefined'; \n" +
" } else if (str == null) { \n" +
" str = 'null'; \n" +
" } \n" +
" var out = context.getWriter(); \n" +
" out.print(String(str)); \n" +
" if (newline) out.print('\\n'); \n" +
" out.flush(); \n" +
"}\n" +
"function println(str) { \n" +
" print(str, true); \n" +
"}";
Scriptable getRuntimeScope(ScriptContext ctxt) {
if (ctxt == null) {
throw new NullPointerException("null script context");
}
// we create a scope for the given ScriptContext
Scriptable newScope = new ExternalScriptable(ctxt, indexedProps);
// Set the prototype of newScope to be 'topLevel' so that
// JavaScript standard objects are visible from the scope.
newScope.setPrototype(topLevel);
// define "context" variable in the new scope
newScope.put("context", newScope, ctxt);
// define "print", "println" functions in the new scope
Context cx = enterContext();
try {
cx.evaluateString(newScope, printSource, "print", 1, null);
} finally {
cx.exit();
}
return newScope;
}
//Compilable methods
public CompiledScript compile(String script) throws ScriptException {
return compile(new StringReader(script));
}
public CompiledScript compile(java.io.Reader script) throws ScriptException {
CompiledScript ret = null;
Context cx = enterContext();
try {
String fileName = (String) get(ScriptEngine.FILENAME);
if (fileName == null) {
fileName = "<Unknown Source>";
}
Scriptable scope = getRuntimeScope(context);
Script scr = cx.compileReader(scope, script, fileName, 1, null);
ret = new RhinoCompiledScript(this, scr);
} catch (Exception e) {
if (DEBUG) e.printStackTrace();
throw new ScriptException(e);
} finally {
cx.exit();
}
return ret;
}
//package-private helpers
static Context enterContext() {
// call this always so that initializer of this class runs
// and initializes custom wrap factory and class shutter.
return Context.enter();
}
void setEngineFactory(ScriptEngineFactory fac) {
factory = fac;
}
Object[] wrapArguments(Object[] args) {
if (args == null) {
return Context.emptyArgs;
}
Object[] res = new Object[args.length];
for (int i = 0; i < res.length; i++) {
res[i] = Context.javaToJS(args[i], topLevel);
}
return res;
}
Object unwrapReturnValue(Object result) {
if (result instanceof Wrapper) {
result = ( (Wrapper) result).unwrap();
}
return result instanceof Undefined ? null : result;
}
public static void main(String[] args) throws Exception {
if (args.length == 0) {
System.out.println("No file specified");
return;
}
InputStreamReader r = new InputStreamReader(new FileInputStream(args[0]));
ScriptEngine engine = new RhinoScriptEngine();
engine.put("x", "y");
engine.put(ScriptEngine.FILENAME, args[0]);
engine.eval(r);
System.out.println(engine.get("x"));
}
}