Webkit tries to download Java applet class before reading it from JAR

Question

I'm embedding a Java applet like this:

<object type="application/x-java-applet">
  <param name="codebase" value="/path/to/jar" />
  <param name="archive" value="myapplet.jar" />' +
  <param name="code" value="my.package.MyClass" />
</object>

The applet works fine in all browsers but Webkit browsers (Chrome and Safari) are both annoying the server with a useless request which tries to download the MyClass file (Which is in the JAR and works fine from there) from the server:

Chrome shows this error in the console:

GET http://localhost/test/my.package.MyClass 404 (Not Found) 

The same happens when using the <embed> tag instead of <object> but it doesn't happen when using the deprecated <applet> tag.

Is there a possibility to prevent this class file downloading somehow? I heard rumors about a codebase_lookup parameter but setting this param to false doesn't change anything.

Penetrate

If you keep control on your application, I suggest just to use the deprecated APPLET tag as it works correctly. Surely support for it may be dropped later but during that time some better solution will probably appear. Surely the things are worse if you hand the application to the your client. – Cockrell

Using the applet tag is not a solution, it's a workaround. I'm hoping for an answer which maybe explains why Webkit is trying to download the class file and how to disable this behavior. Maybe it is a Webkit bug and someone knows the location of a bug report which contains more information about this issue. Who knows. – Penetrate

Yes, it is a workaround, not an answer. – Cockrell

Use deployJava.js for writing the applet/object element. – Birdseed

Have you tried to use jar://myapplet.jar!my.package.MyClass as code? I think this should be the correct URL for classes inside a Jar. Maybe, the webkit will drop the request to a jar:// url. I am pretty unsure about this, so I don't want to give this as an answer. – Conatus

Just another question: WHY don't you want to use the applet-tag? – Conatus

Applet-tag is no longer supported in HTML5: w3schools.com/tags/tag_applet.asp – Diplodocus

Answer 1

I found that this issue occurs when applet's code parameter is set in the param tag. If you move it to the corresponding object's attribute, 404 error no longer appear:

<object type="application/x-java-applet" code="my.package.MyClass">
   <param name="codebase" value="/path/to/jar" />
   <param name="archive" value="myapplet.jar" />
</object>

Tested on:

Windows 8, Java 1.7.0_25: Chrome 28, Firefox 23, IE10

OS X 10.6.8, Java 1.6.0_51: Chrome 28, Firefox 23, Safari 5.1.9

OS X 10.7.5, Java 1.7.0_25: Firefox 23, Safari 6.0.5

OS X 10.8.4, Java 1.7.0.25: Firefox 23, Safari 6.0.5

OS X 10.9, Java 1.7.0_25, Firefox 23, Safari 7.0

Franchot