For Ubuntu (16.04):

Install Java and Java Webstart command

$ sudo apt install default-jre icedtea-netx

(default-jre is the Java Run-Time Environment; icedtea-NetX is an implementation of the Java Network Launching Protocol (JNLP) and includes javaws - the command to launch a Java Webstart app)

Options:

A) From Firefox: launch a WebStart file directly from your browser

To do this, you need to update your FireFox preferences to associate the ".jnlp" file suffix with Java Webstart Command

1. Launch Mozilla Firefox;
2. Select Preferences;
3. Select Applications;
4. Under Content Type, locate the entry for JNLP File.  Use can search for the "jnlp" entry;
5. Enter full path to you javaws

(use: "whereis javaws" from command line to find path)

The association is complete.  You can now launch the Voxforge SpeechSubmission app directly from Firefox.  Simply click on the WebStart link on the VoxForge read page, and follow the instructions.

B) From Command line:

You can run a .jnlp file from a web server and run it directly from the command line:

$ javaws http://read.voxforge1.org/speech/SpeechSubmission.jnlp

-or-

download the .jnlp file to your computer first, and then run it locally:

$ javaws SpeechSubmission.jnlp