Marvin Applets Frequently Asked Questions

• Which Java versions are supported by Marvin applets?
• Which files are required to run Marvin applets?
• How can I create a jar file that contains all necessary classes for Marvin applets?
• How can I delete plugin packages from the Marvin applets package?
• How can I create an unsigned jar file from a signed jar file?
• How long is the signed applet valid?

• If I put MView applets in an HTML table then I can display only about 200 molecules because the browser slows down and runs out of memory. Do you provide a simple and "thin" applet, which just displays molecules without any rotation and linkage to the sketcher?
• I have not managed to load a molecule string from applet parameter in Mozilla.

• How can I set the Java environment of Netscape in Linux?
• IE can not load Marvin applets over SSL communication. I have got this warning message: "This page contains both secure and non-secure items."

To see further questions, visit the following pages:

• Notes for Mac users
• Crashes, freezes and other bugs FAQ

• Which Java versions are supported by Marvin applets?

  ChemAxon products support only Sun distributed Java. On Mac platform (where Sun Java is not available), our products support Apple's built-in Java that is compatible with Sun's distribution. Marvin applets requires at least Java 1.5.

• Which files are required to run Marvin applets?

  Several packages can be downloaded from the Marvin site:

  • marvin-bin-5.0.0alpha12.tar.gz or marvin-bin-5.0.0alpha12.zip

    Download and unpack:

    zip: unzip marvin-bin-5.0.0alpha12.zip
    tar.gz: gunzip < marvin-bin-5.0.0alpha12.tar.gz |tar xf -

    This distribution contains all files necessary for using MarvinSketch and MarvinView applets, without HTML pages and examples.

  • marvin-all-5.0.0alpha12.tar.gz and marvin-all-5.0.0alpha12.zip

    Download and unpack:

    zip: unzip marvin-all-5.0.0alpha12.zip
    tar.gz: gunzip < marvin-all-5.0.0alpha12.tar.gz | tar xf -

    This distribution contains all files necessary for using MarvinSketch and MarvinView applets, as well as the documentation and examples.

• How can I create a jar file that contains all necessary classes for Marvin applets?

  • Create jmarvin.jar

    The following jar files should not be modified because they are signed jars. If you do so, the modified jar is no longer signed.

    1. Download and unpack marvin-bin-5.0.0alpha12.tar.gz or marvin-bin-5.0.0alpha12.zip.
    2. Create a new directory: marvintmp
    3. Unzip jmarvin.jar and every jar file from sjars directory and its subdirectories to the new directory:

       	    unzip -o jmarvin.jar -d marvintmp
       	    unzip -o sjars/abbrevgroupexport.jar -d marvintmp
       	    unzip -o sjars/batik-core.jar -d marvintmp
       	    unzip -o sjars/clean2d.jar -d marvintmp
       	    ...
       	    

    4. Change location to the new directory and create a new jar file:

       	    cd marvintmp
       	    zip jmarvin.jar *
       	    

    Note: If you do not need SVG export, sjars/batik-core.jar can be skipped.

• How can I delete plugin packages from the Marvin applets package?

  Remove chemaxon/marvin/plugin and sjars/plugin directories from the marvin directory.

      cd marvin
      rm -r chemaxon/marvin/plugin
      rm -r sjars/plugin
      

• How can I create an unsigned jar file from a signed jar file?

  Unzip the signed jar file into an empty directory. Delete signing information from the META-INF directory. Finally, create a new jar file with the content of the directory.
  For example creating the unsigned version of the the signed jmarvin.jar file under Linux:

  	unzip -d targetdir jmarvin.jar 
  	cd targetdir
  	rm -f META-INF/CHEMCERT.*
  	zip jmarvin.jar *
      

  Under Linux and Unix, you can run unsigner.sh to unsign signed jar files in Marvin:

  	cd marvin
  	./unsigner -a
      

• When I put MView applets into an HTML table, I can only display about 200 molecules because the browser slows down and runs out of memory. Do you provide a simple and "thin" applet, which just displays molecules without any rotation and linkage to the sketcher?

  The rotation and the linkage to the sketcher have negligible contribution to the memory footprint. The largest contributions are from

  1. double buffering of Swing components
  2. size of Molecule objects
  3. large color arrays that store the shades for 3D rendering modes

  Even if we provided a "thin" applet without 3D support, it would only enable you to use about twice as many molecules. Then you would run out of memory again because of the double buffering.

  You should use an n-molecule scrollable MView table instead of n applets. Then the common data will be stored in only one place (instead of n) and the number of Swing components will be equal to the number of visible molecules which is usually much smaller than n.

• I have not managed to load a molecule string from applet parameter in Mozilla.

  Your molecule string may contain consecutive space characters in applet parameters which are converted to only one space. This bug applies to Mozilla 0.9.7-1.0 and probably some earlier versions too.

• How can I set the Java environment of Firefox in Linux?

  See the documentation of Sun's Java: Manual Installation and Registration of Linux Plugin

• IE can not load Marvin applets over SSL communication. I have got this warning message: "This page contains both secure and non-secure items."

  The CODEBASE attribute of the OBJECT tag refers to a non-secure page that the browser does not accept. The browser downloads the plugin from this URL, if the Java Plugin is not installed on your machine.
  You should change this URL to a secure one.
  1. To provide a secure page for downloading a Java Plugin, copy a JRE cab file to your site.

     http://java.sun.com/products/plugin/autodl/jinstall-1_4_2-windows-i586.cab#Version=1,3,0,0
     

  2. Modify the reference to this cab file in marvin.js. (Search the following code in the applet_begin function).

     s += ' CODEBASE=" http://java.sun.com/products/plugin/autodl/jinstall-1_4_2-windows-i586.cab#Version=1,3,0,0"\n';
     

     You should replace the text with

     s += ' CODEBASE=" https://<PLUGINLOCATION>/jinstall-1_4_2-windows-i586.cab#Version=1,3,0,0"\n';
     

     where <PLUGINLOCATION> is the new location of the cab file (e.g.: www.my_secure_site.com/java_plugin). Note: The new URL must start with "https" protocol instead of "http".

• How long is the signed applet valid?

  Read the following document, to check the expiration date of signing for Marvin applets: Expiration date of releases.