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6.5 Applet Component

The Applet Component contains an entry for each of the applets defined in this package. Applets are defined by implementing a non-abstract subclass, direct or indirect, of the javacard.framework.Applet class.<SUP>[2]</SUP> If no applets are defined, this component must not be present in this CAP file.

The Applet Component is described by the following variable-length structure:

The items in the applet_component structure are as follows:


The tag item has the value COMPONENT_Applet (3).


The size item indicates the number of bytes in the applet_component structure, excluding the tag and size items. The value of the size item must be greater than zero.


The count item indicates the number of applets defined in this package. The value of the count item must be greater than zero.


The applets item represents a table of variable-length structures each describing an applet defined in this package.

The items in each entry of the applets table are defined as follows:


The AID_length item represents the number of bytes in the AID item. Valid values are between 5 and 16, inclusive.


The AID item represents the Java Card platform name of the applet.

Each applet is assigned an AID conforming to the ISO 7816-5 standard ( Section 4.2, AID-based Naming). The RID (first 5 bytes) of all of the applet AIDs must have the same value. In addition, the RID of each applet AIDs must have the same value as the RID of the package defined in this CAP file.


The value of the install_method_offset item must be a 16-bit offset into the info item of the Method Component ( Section 6.9, Method Component). The item at that offset must be a method_info structure that represents the static install(byte[],short,byte) method of the applet.<SUP>[3]</SUP> The install(byte[],short,byte) method must be defined in a class that extends the javacard.framework.applet class, directly or indirectly. The install(byte[],short,byte) method is called to initialize the applet.

javacard/jcvm/6.5_applet_component.txt · Last modified: 2017/05/13 04:10 (external edit)