First, read and agree to the license, then click the button below to download and run the Hades editor via the Java Webstart launcher.

Notes for JDK8 and up (29/Dec/2018)

So; even if your Java runtime still includes Java webstart, you may encounter problems running the webdemos on this site. Depending on your particular version of Java, and your default settings in the Java control panel, you may be prompted with several security warnings:

• The hades.jar archive with the actual simulator software still uses a self-signed (and perhaps even expired) certificate. It is your choice to accept that certificate - or not.

  Note: We considered using an certificate from the University, with a trust chain rooted at Telekom Germany. That would be one less warning for you, but the actual security would still be the same...

• Recent versions of Java Webstart introduced new properties, including the permission attribute, which are missing from the jnlp files on this site. You may be prompted with another security warning. Say yes.

• Finally, in an attempt to protect against man-in-the-middle attacks, recent versions of Java webstart also double-check the codebase attribute. Unfortunately, for historical reasons, our jnlp files specify codebase as the actual URL of the individual demos, e.g. codebase="https://tams.informatik.uni-hamburg.de/applets/hades/webdemos/00-intro/00-welcome/", while the software is loaded from ../webdemos/classes/hades.jar. You might get another security prompt for this.

• On Linux distros like Ubuntu, you probably have an OpenJDK installed. This by default comes without the Java webstart support, which is provided by a separate software package. If not installed, you might want to install the corresponding add-on to the JDK, e.g. sudo apt-get install icedtea-netx.

Notes about Java Webstart

To actually run the editor after download, you have to ignore the warning about self-signed certificates being insecure. If you don't trust this, you can download the Hades software archive manually from our download page. However, this incurs an even higher risk than using Webstart, because the software integrity is not checked at all.

You can configure the behaviour of the Webstart launcher via the Java Webstart control panel. For example, you can disable the automatic download of new software versions via the control panel, if your internet connection is slow. On Windows, the Webstart launcher can optionally also create start-menu entries and desktop icons for Hades; just agree to this when prompted by Webstart.

What's next?

To access the built-in examples, open the help menu, select demos, and then select one of the example circuits. The examples include a few simple circuits meant to demonstrate the basic functions of the simulator and user-interface, and a few demos typically used for courses on basic digital system design. Please check our download page and the website applet collection for other example circuits.

If you allowed Java webstart to create a desktop icon or start-menu entries, you can start Hades later via clicking those. Otherwise, just visit this web page again and click the button above to start Hades. Of course, the Webstart launcher will not download the software again (unless you deleted Hades from your Webstart cache, or an updated version of Hades is available). Finally, you can also start Hades via the Java Webstart configuration tool.

Please note that the Webstart launcher is configured to always start the Hades schematics editor as the main application. If you want to run one of the several smaller applications included in the Hades class archive file, you can use the Java webstart control application to create the required setup information (the name of the main class, e.g. hades.models.pic.PicAssembler, and parameters). Please check your Java virtual machine documentation for details about how to use the webstart configuration tool.

However, if you plan to integrate Hades into your own software environment (e.g. Eclipse), it might be better to simply download the Hades class archive (hades.jar) again from our download page. Please check the Hades tutorial for details about the required and/or recommended CLASSPATH settings etc.