Calling the applet from Javascript

[sderrick]

I'm having intermittent crashes when calling the applet to load up a file and am sure its something I'm not doing right.

I see two different methods used..

this one elevates privileges

Code: Select all

 public String getSerializedDocument() {

        //EXM-27477 This method might come from Javascript code, elevate privileges.

        return AccessController.doPrivileged(new PrivilegedAction<String>() {

            @Override

            public String run() {

                StringBuilder builder = new StringBuilder();

                BufferedReader reader = new BufferedReader(editorComponent
    

this one calls runnable, elevates privileges and waits on a thread.

Code: Select all

	public void setDocumentContent(final String url, final String xmlContent)

            throws AuthorComponentException {

        documentURL = url;

        Runnable runnable = new Runnable() {

            @Override

            public void run() {

                //EXM-27477 This method might come from Javascript code, elevate privileges.

                AccessController.doPrivileged(new PrivilegedAction<String>() {

                    @Override

                    public String run() {

                        invokeOnAWT(new Runnable() {

                            @Override

                            public void run() {

1.) Why the difference?

2.) If I add a function which should I use?

3.) If I return a value there is no built in thread accessors?

4.) What happens if these get stacked? elevate, calls another elevate?

thanks,

Scott

[sderrick]

I cleaned up and combined the function calls into the applet from javascript, and so far that has ended the odd crash.

Though I haven't been able to run the applet from a remote server yet to really test it. It did appear to be timing or thread issues..

Scott

[Radu]

Hi Scott,

I am not sure why those crashes occurred, did you find any meaningful information in the Java console view?
From what I remember, when the Javascript code calls the applet code, it calls it with restrictive security permissions so we elevated the rights in the Java code.
An alternative to elevating the rights in the Java functions called from JS would have been to call System.setSecurityManager(null); early when the applet was started.

Regards,
Radu

[sderrick]

Radu,

When it happened, The browser would hang, no output in the console. When it would finally recover the console would close, and the web page would report the plugin had crashed.

If it happens again I will enable logging in the java control panel.

Scott