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4.3.4 References - External and Internal

In the context of a CAP file, references to items are made indirectly through a package's constant pool. References to items in other packages are called external, and are represented in terms of tokens. References to items in the same CAP file are called internal, and are represented either in terms of tokens, or in a different internal format.

An external reference to a class is composed of a package token and a class token. Together those tokens specify a certain class in a certain package. An internal reference to a class is a 15-bit value that is a pointer to the class structure's location within the CAP file.

An external reference to a static class member, either a field or method, consists of a package token, a class token, and a token for the static field or static method. An internal reference to a static class member is a 16-bit value that is a pointer to the item's location in the CAP file.

References to instance fields, virtual methods and interface methods consist of a class reference and a token of the appropriate type. The class reference determines whether the reference is external or internal.

javacard/jcvm/4.3.4_references_-_external_and_internal.txt · Last modified: 2017/05/13 04:11 (external edit)