Using an Older Java Runtime

The final option to InstallJava is Java1. Set Java1->True if you are using a Java runtime with a version number of 1.1.x (when Java went to version 1.2, it was a major upgrade called "Java 2.") In Mathematica 4.2 and later, the bundled Java runtimes are all at version 1.3 or later, so this option will not be useful to the vast majority of users. However, there are some older versions of Unix operating systems for which no Java 1.2 or later runtime is available (HP-UX 10.20 is the most important example). If you are forced to use an Java 1.1 runtime, you must set Java1->True in InstallJava. You must also take the extra installation step of making sure that the full path to JLink.jar is included in your CLASSPATH environment variable. Please note that support for Java runtimes earlier than version 1.2 will be dropped in future versions of J/Link.