Most of the classes in the java.lang package are not supported on the Java Card platform. The following classes from java.lang are supported on the card in a limited form.

Java Card API classes descend from java.lang.Object, just as in the Java programming language. Most of the methods of Object are not available in the Java Card API, but the class itself exists to provide a root for the class hierarchy.

Class Throwable and its subclasses are supported. Most of the methods of Throwable are not available in the Java Card API, but the class itself exists to provide a common ancestor for all exceptions.