The file is a standard Java™ properties file that enables you to specify default properties of your Java environment.

This file may be used to send in both JVM properties and JVM options. Previously only JVM properties were supported. To also allow JVM options, the first line of the file must contain "#AllowOptions" or else everything will be treated as a JVM property.

The file that resides in your home directory takes priority over the file that resides in the /QIBM/UserData/Java400 directory.

Properties that you set in the /YourUserHome/ file affect only the following specific Java virtual machines:

  • JVMs that you start without specifying a different user.home property
  • JVMs that others users start by specifying the property user.home = /YourUserHome/

Example: file

The following example sets several Java properties and options:

#Comments start with pound sign
The Java properties and options above affects the JVM in the following way:
  • There are four properties: prop1, prop2, prop3, and prop4.
  • The max heap size is 200 MB.
  • The JIT will not be used.

If the #AllowOptions line is removed from the example above, then the JVM would contain six properties: prop1, -Dprop2, -Dprop3, -Xms200m, prop4, and -Xnojit.