Java for Apple
One generally starts a Java WebStart application by clicking on a link in a web browser. WebStart is typically registered as the helper application for content with mime type application/x-java-jnlp-file , so the browser downloads the jnlp content and hands it off to WebStart. Depending on configuration, desktop shortcuts may be installed to speed up subsequent launches, and cached applications can also be launched from within the WebStart control panel. On occasion, though, it is useful to launch WebStart “manually” from the command line, without the overhead of getting a web browser involved. The most straightforward way to do this is to simply use the “ javaws ” command included in the JDK. This is located in the “ bin ” directory in Linux and Windows distributions of the JDK or JRE.
Java for Mac OS X 10.5 Update 4 delivers improved reliability, security, and compatibility for Java SE 6, J2SE 5.0 and J2SE 1.4.2 on Mac OS X 10.5.7 and later. This release updates Java SE 6 to version 1.6.0_13, J2SE 5.0 to version 1.5.0_19, and J2SE 1.4.2 to 1.4.2_21. Please quit all web browsers before installing this update.
About Java : https://devforums.apple.com/community/mac/languages/java by Nov 12