The . operator provides a mechanism for accessing fields and methods of instances of Java classes. It is intended to work as closely to similar constructs in the Java language as possible.
The first syntax example returns the variable that is the field specified within the object instance. If the field specified is final, the value of the specified field within the object instance is returned.
The second syntax example returns the value returned by the method specified, which must exist in the class of which objectIdentifier is an instance.
If fieldIdentifier or methodIdentifier is not a member of the of the class, or the value of the objectIdentifier is NULL, an !ERROR=17 is returned.