There are several Java Versions available for free download on the Sun Website.
Translator is fully functional under the JRE 1.4, but runs as well under JRE 1.3 (with minor problems).
You have the choice to download either the:
JRE (Java Runtime Environment):
This contains all files required to run Java software.
Download size ~ 9MB
SDK (Software Development Kit) The Java SDK contains all files to develop Java programs, as well as the complete JRE.It is only interesting for programmers.
Download size ~ 36 MB