Finding Embedded Documents in Conjunction with the Object Tag

Java Applet embedded with the object tag

<OBJECT classid=java:Struppi.class data=segue.gif height=150 id=obj1 width=80
      archive="data.jar, data2.jar, data3.jar" border="1">
</OBJECT>

identifying attribute id=obj1

  1. attribute classid contains classfile, this class file doesn't exist, the server responds with http error 404
  2. attribute data holds a picture that has to be downloaded
  3. attribute archive holds three jar files that have to be downloaded

Class file not found or Your browser doesn't support java

The class file doesn't exist, therefore the applet wasn't started

Embedded ActiveX controls
  1. Maybe Netscape can't render those ActiveX controls
    but it detects as well that it has to download file 'box1.gif'
    specified in the first ActiveX control example.
  2. It hardly happens that ActiveX controls invoke downloads because the source for such controls exists on the client machine.
    A download will only be performed when the source doesn't exist on the client machine and the path where the source can be
    downloaded was specified in the object attribute.
  3. Such a seldom download could simply be recorded with function WebPageUrl

The first ActiveX control:
All of this object tag may be ignored except thedata attribute

<OBJECT classid=CLSID:DFD181E0-5E2F-11CE-A449-00AA004A803D data= box1.gif>  
       height=65 id="Microsoft Forms 2.0 ScrollBar" width=110>
</OBJECT>

The second ActiveX control:
Simply ignore the whole object tag


<OBJECT classid=CLSID:8E27C92B-1264-101C-8A2F-040224009C02 height=30
id="Calendar Control 8.0" style="HEIGHT: 163px; WIDTH: 300px" width=80>
</OBJECT>

 

Alternative loading (Netscape behaves different)

IExplorer parses the first object tag, detects 'classid=SnakeRattle' and tries to download the file.
Netscape detects 'classid=SnakeRattle' and recognizes that no program, to interpret SnakeRattle.py, was specified.
Netscape simply ignores the first object tag.

<OBJECT classid=SnakeRattle.py id=FakeObject>       <!-- if we cannot download 'SankeRattle.py'-->
      <OBJECT classid=java:Viewer.class id=obj8 >       <!-- then we have to download 'Viewer.class' -->
          <PARAM NAME="picture" VALUE="segue2.gif">
      </OBJECT>
</OBJECT>

Nested object tags:
The browser request for the file 'SnakeRattle.py'. The server returns the errorcode 404 (not found)
then the broser have to download the alternative 'Viewer.class'.

 

You should look for better browsers!!!!!!

Alternative loading

<OBJECT classid=tschawa:SnakeRattle.py id= FakedAgain >
    <OBJECT classid=java:Suppi.class id= obj5 >
    </OBJECT>
</OBJECT>

The browser checks the first object tag and notices that it can't support a programm called 'tschawa'. Therefore,
the browser continues and tries to download 'Suppi.class'.


 

 

Displayed instead of the applet

 

The response of the server has to be again http error 404 (not found). The class wasn't implemented.