Accessing Java Privileged Actions from within Rhino script - java

How can I execute a local file from JavaScript running within Rhino in Java? I will consider any method that works from within the Rhino environment. My current exploration of the issue is below.
I am attempting this through java.lang.Runtime.exec, with help from the Mozilla "Scripting Java" tutorial i can access it. However this is a restricted action so calling it directly gives an access control exception.
To solve this I need to use the AccesController.doPrivileged method. An example of using this in Java is below;
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
// Code goes here. Any permission checks within this
// run method will require that the intersection of the
// callers protection domain and the snapshot's
// context have the desired permission.
}
The road block is replicating the construction of a PrivilegedAction in javascript.
var ourRuntime = Packages.java.lang.Runtime.getRuntime();
//ourRuntime.exec("notepad.exe") //will raise Access Control Exception
var controller = Packages.java.security.AccessController.doPrivileged
var action = new Packages.java.security.PrivilegedAction(ourRuntime.exec("notepad.exe")) // somehow make this wwrk
controller.doPrivileged(action)
Mozilla Scripting Java
java.securit.AccessController

Rhino is supported by Java 6 scripting API, so you can wrap eval of your script with doPrivileged and execute entire script with necessary permissions. Example of java scripting API combined with doPrivileged is here

I've had success starting KWrite (for example) this way. I basically expose the Runtime object to the embedded JavaScript interpreter.
public class RunBasicScript {
public static void main(String[] args) {
// Get a handle to the JavaScript context
Context cx = Context.enter();
try
{
// Set up the standard JavaScript objects
// like Object, Function etc.
Scriptable scope = cx.initStandardObjects();
// Make Runtime.getRuntime available to our JavaScript code
Object exec = Context.javaToJS(Runtime.getRuntime(), scope);
ScriptableObject.putProperty(scope, "exec", exec);
// Build our awesome script
String script = "exec.exec('kwrite');";
// Now we execute the script
Object obj = cx.evaluateString(scope, script, "Testing", 1, null);
}
catch (Exception e)
{
System.err.println("Error : " + e);
}
finally
{
// We need to exit the Context.
Context.exit();
}
}
}

Related

How to run a Google App Script using Google API Service Library (Java)

By following the Java Quickstart example, I am able to create a new Google App Script project and retrieve the scriptId. Also, by referring to the Restful API document, the script should be able to be executed using Method: scripts.run. However, I don't know how to retrieve the return value using com.google.api.services.script.Script in Java.
I've tried:
Script scriptService = getScriptService();
Script.Scripts scripts = scriptService.scripts();
Script.Scripts.Run run = scripts.run(scriptId, request);
and decompiled run function:
public Script.Scripts.Run run(String var1, ExecutionRequest var2) throws IOException {
Script.Scripts.Run var3 = new Script.Scripts.Run(var1, var2);
Script.this.initialize(var3);
return var3;
}
The function doesn't return an ExecutionResponse object which I am looking for.
Per the REST API documentation, calling script.run does not immediately return an ExecutionResponse object, but an Operation object that may contain an ExecutionResponse:
{
"done": boolean,
// Union field result can be only one of the following:
"error": {
object(Status)
},
"response": object(ExecutionResponse)
,
// End of list of possible types for union field result.
}
If we look at the Java API Client library, we see that method Script.Script.run takes arguments of the script ID, and an ExecutionRequest, and then returns a Script.Script.Run request that must be .execute()d:
Create a request for the method "scripts.run". This request holds the parameters needed by the script server. After setting any optional parameters, call the AbstractGoogleClientRequest.execute() method to invoke the remote operation.
The request referred to by the quoted documentation is Script.Script.Run, and has methods like .setAccessToken() for additional configuration, and several execution methods like .execute() and .executeMedia() to actually submit the execution request and return the Operation.

JavaFX+WebView/Javascript : setTimeOut does not work call stack comes from Java

I have a JavaFX application that loads my own HTML/JS application in a WebView. Depending on the event, I need to call Javascript from Java, and Java from Javascript.
Every is good when going from JS to Java but I've got weird behaviors when going from Java to Javascript.
Here's, basically, how I setup the communication between the 2 languages:
_
var javaObjectInjected = typeof javaObject !== "undefined";
if(javaObjectInjected && !javaObjectInitialized) {
jThalesEventBusInitialized = true;
const jsAdapter = {
publishToJs: onPublishToJs
};
javaObject.setJsAdapter(jsAdapter);
}
My Java code will invoke the method publishToJs on the provided jsAdapter. This will result in the execution of onPublishToJs.
_
function onPublishToJs(topic, data) {
alert('Yeah! We are inside JS'); //output_1
setTimeout(
function() {
alert('inside setTimeOut'); //output_2
},
1000
);
}
I do get output_1 but not output_2. It's like the callback on setTimeOut was discarded.
Are there any known limitations when invoking JS from Java?
I refactored my code and instead of injecting jsAdapter to the Java world using javaObject.setJsAdapter(jsAdapter), I exposed jsAdapter to Java as a new member of window.
With this new code structure, I got exceptions when invoking jsAdapter from Java because I was doing it from the EDT instead of the JavaFX Application Thread.
Eventually, I wrapped the jsAdapter calls in Platform.runLater(() -> ...) and that was it.
When working with Javascript loaded from a JavaFX WebView, make sure to always perform Javascript calls from the JavaFX Application Thread.

JavaScript scope resolve time

I'm writing an app that loads javascript dynamically using rhino(or a browser); I got 2 files:
// in a file called fooDefinition.js
var definition = {
foo: function(data){return bar(data)},
loadFile: "barLib.js"
}
now, bar() is defined like this:
// in a file called barLib.js
function bar(data){
return data + " -> bar!";
}
This is what I want to do:
load fooDefinition.js into the environment
read the value of loadFile (in this case: "barLib.js") and load the file (NOTE: load the file through external mechanism, not through javascript itself!)
call foo
external mechanism & example usage (Java pseudo code):
// assume engine is a statefull engine (rhino for example)
String str = /*content of fooDefinition.js*/;
engine.eval(str);
String fileToLoad = engine.eval("definition.loadFile");
engine.load(IOUtils.readFileToString(new File(fileToLoad)));
String result = engine.eval("definition.foo('myData')");
I've tried this in Google Chrome's JS console and no error was thrown
I wonder is this the correct way of accomplish such task?
TL;DR:
Are the attributes of an object loaded and checked when the object is defined?
If your engine is statefull that is it keeps track of defined variables, yes your approach is corrent and will work as expected
But if it is not, your way will fail, because when you call the following
String fileToLoad = engine.eval("definition.loadFile");
your engine haven't any info about definition object and as a result it return an exception (in JavaScript).
It seems your engine is statefull and all things will work correctly

Use ScriptEngine to bind global javascript functions from java code [duplicate]

The JSR223 Bindings class allows you to expose arbitrary Java objects to scripting languages. But they have to be objects. I would like to define a function quit() that can be called from the scripting environment that turns into quitObject.run() in Java. But JSR223 doesn't define the concept of a function object. Is there a language-independent way to do the following in Javascript, namely to take a Runnable() and create a function in the scripting environment?
static private Object asFunction(ScriptEngine engine, Runnable r)
throws ScriptException
{
final Bindings bindings = engine.createBindings();
bindings.put("r", r);
return engine.eval(
"(function (r) { var f = function() { r.run(); }; return f;})(r)",
bindings);
}
Runnable quitObject = /* get/create a Runnable here */
Bindings bindings = engine.createBindings();
bindings.put("quit", asFunction(engine, quitObject));
With the builtin Javascript support for JSR223 this creates a sun.org.mozilla.javascript.internal.InterpretedFunction which does what I want. But it obviously won't work in Jython or whatever, and I'd like to make this language-independent.
I don't want my script users to have to type quitObject.run() as that's clumsy, and I don't want to parse script input to find quit() as it could be buried within other code.
If you look at javascript engine source code you'll find how oracle/sun implemented 2 functions (print, and println) which are magically (or not so magically) present when you fire up your engine.
Those function are 'scripted' , which is more or less what you did.
What I would do is : load and evaluate a bootstrap.[language_extension] before evaluating any other input in the new context.
You could easily create such scripts for each language you intend to support.

How to run vbscript function from java?

From java code i am able to run the vbscript by using this code
Runtime.getRuntime().exec("wscript C:\\ppt\\test1.vbs ");
But want to know how to call the method of vbscript from java..for example in test1.vbs
Set objPPT = CreateObject("PowerPoint.Application")
objPPT.Visible = True
Set objPresentation = objPPT.Presentations.Open("C:\ppt\Labo.ppt")
Set objSlideShow = objPresentation.SlideShowSettings.Run.View
sub ssn1()
objPPT.Run "C:\ppt\Labo.ppt!.SSN"
End sub
how to call only ssn1() method from java.Otherwise can we run the macro of a power point from java code..kindly help!!
This should make you happy :) Go to the WScript section : http://technet.microsoft.com/library/ee156618.aspx
Here's my idea... in your vbscript file, make your script listen to a command line parameter that would specify which method to call. Then, in Java, you could only have to use this parameter whenever you want to call a specific method in the file.
Otherwise, if you want to access powerpoint in java, you will need to access its API like you did in vbscript, which is possible if vbscript can do it but the approach / syntax may change.
I'm not so much into the visual basic script side, but if you can expose your visual basic script as a COM object, the you can access the methods of it from java by usage of frameworks such as for example com4j:
http://com4j.java.net/
The PowerPoint application object's .Run method lets you call any public subroutine or function in any open presentation or loaded add-in
This post answers the OP's question:
Otherwise can we run the macro of a power point from java code..kindly help!!
(but does not address the original vbscript question)
There's the JACOB library, which stands for Java COM Bridge, you can find here: http://sourceforge.net/projects/jacob-project/?source=directory
With it you can invoke Excel, Word, Outlook, PowerPoint application object model methods.
I've tried this with Excel but not PowerPoint. (This is just some sample code, one might want to make it more object oriented.)
public class Excel {
private static ActiveXComponent xl = null;
public static Init() {
try {
ComThread.InitSTA();
xl = ActiveXComponent.connectToActiveInstance("Excel.Application.14");
// 14 is Office 2010, if you don't know what version you can do "Excel.Application"
if (xl==null) {
// code to launch Excel if not running:
xl = new ActiveXComponent("Excel.Application");
Dispatch.put(xl, "Visible", Constants.kTrue);
}
}
catch (Exception e) {
ComThread.Release();
}
}
public static String Run(String vbName) {
// Variant v = Dispatch.call(xl, "Run", vbName); // using string name lookup
Variant v = Dispatch.call(xl, 0x103, vbName); // using COM offset
// return Dispatch.get(this, "Name").getString();
return v.getString();
}
public static Variant Run1p(String vbName, Object param) {
// Variant v = Dispatch.call(xl, "Run", vbName, param);
return Dispatch.call(xl, 0x103, vbName, param);
// return Dispatch.get(this, "Name").getString();
}
public static Worksheet GetActiveWorksheet () {
// Dispatch d = xl.getProperty("ActiveSheet").toDispatch();
Dispatch d = Dispatch.get(xl, 0x133).toDispatch ();
return d; // you may want to put a wrapper around this...
}
}
Notes:
For Excel, at least, to get Run to invoke a VBA macro/subroutine several things have to be true:
The Excel workbook containing the macro must be "Active" (i.e. must
be the ActiveWorkbook) otherwise Run will not find the VBA subroutine. (However the workbook does not have to be
screen visible!! This means you can call a VBA Macro that is in an add-in!).
You can then pass the name of the macro using the following syntax as a string literal:
VBAProjectName.VBAModuleName.SubroutineName
For COM object invocations, you can use the name lookup version or the id number version. The id numbers come from the published COM interfaces (which you can find in C++ header files, or possibly have JACOB look them up for you).
If you successfully did the connection to Excel, be sure to call ComThread.Release() when you're done. Put it in some appropriately surrounding finally. If the process of your Java code terminates without calling it, the COM reference count on Excel will be wrong, and the Excel process will never terminate, even after you exit the Excel application. Once that happens, needless to say, Excel starts to behave screwy then (when you try to use it next, it runs but will fail to load any plug-ins/add-ons). If that happens (as it can during debugging esp. if you are bypassing finally's for better debugging) you have to use the task manager to kill the Excel process.

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