Chapter 2 – The Muddy Client

The Muddy client is a HTML mud client written using the HTMLEditorKit and its associated classes.  It sends a special command to the Mud server on startup and the Mud server will then supply HTML output rather than the text output of a traditional Mud.

 

 

Starting the Client with Web Start

The Muddy client is started with Java Web Start .  Java Web Start is included in JDK 1.4 and is a separate product in JDK 1.3.   Java Web Start is a tool that allows you to distribute executable Jar files through web pages.  It frees the web application from the bounds of HTML and allows you to write Internet clients in Swing.  You must configure your Web Start application to user JDK 1.4.   If you have installed a Beta version, you need to add a version that is not marked with the “-beta” suffix.  It should be the most recent version and should have Product Version equal to 1.4.0.

 

 

Preparing a Jar for Web Start

The Muddy client Jar must be signed in order for it to start properly.  Signing a Jar essentially just provides a marker that says, “This is where I came from.”  It protects your users from downloading malicious code unknowingly. 

 

Before you can distribute the Muddy client, you must generate a key and sign the jar.  A program to generate keys comes with JDK 1.4.  To generate the key, use the following:

 

 keytool -genkey -keystore muddyKeys -alias owlmountain

 

You get a dialogue where you create a key store.  Don’t use the same password as the demo, but instead your own secret password.  You will want to modify the build file to contain this password.  Say your password was “muddy123”.  Change build.xml so that it signs the muddy client and all the dependent jars.

 

    <!-- Sign the client -->

    <target name="muddy-signed" depends="muddy,web-libs">

        <signjar jar="${lib.dir}/web/${muddy.jar}"

                 keystore="muddyKeys"

                 storepass="muddy123"

                 keypass="muddy123"

                 alias="owlmountain"/>

 

        <signjar jar="${lib.dir}/web/xerces.jar"

                 keystore="muddyKeys"

                 storepass="muddy123"

                 keypass="muddy123"

                 alias="owlmountain"/>

 

        <signjar jar="${lib.dir}/web/js.jar"

                 keystore="muddyKeys"

                 storepass="muddy123"

                 keypass="muddy123"

                 alias="owlmountain"/>

 

        <signjar jar="${lib.dir}/web/ss_css2.jar"

                 keystore="muddyKeys"

                 storepass="muddy123"

                 keypass="muddy123"

                 alias="owlmountain"/>

    </target>

 

 

Now try and launch the client from the web page.  Sometimes the WebStart cache doesn’t work and you have to launch twice, but once the configuration is correct, it works great.