jCardSim includes two classes which run an instance of the simulator directly from the command line:

• APDUScriptTool reads command APDUs from a file and writes the response APDUs
• BixVReaderCard connects to a PC/SC virtual reader

Using APDUScriptTool

Start parameters:

java -cp jcardsim-2.2.2-all.jar com.licel.jcardsim.utils.APDUScriptTool <jcardsim.cfg> <apdu script> [out file]

jcardsim.cfg, is a file with settings for the simulator. In it you can set information about your applets. It has the following format:

com.licel.jcardsim.card.applet.{index}.AID=<Applet AID>
com.licel.jcardsim.card.applet.{index}.Class=<Applet ClassName>

where {index} is a number from 0 to 10.

To simplify the development and debugging process, jCardSim works directly with class files. You do not need to convert your Java Card applet to CAP in order to use it in the simulator. NOTE: Applet classes and their dependencies must be in the class path when the simulator starts.

An example settings file:

com.licel.jcardsim.card.applet.0.AID=010203040506070809
com.licel.jcardsim.card.applet.0.Class=com.licel.jcardsim.samples.HelloWorldApplet

<apdu script> - file with APDU commands in C-APDU format. This file is compatible with the script format of apdutool from the Java Card Development Kit.

C-APDUs ends with ; and comments begin with //.

APDU commands can be represented by DEC or HEX characters. HEX characters start with 0x. One APDU command (C-APDU) can span multiple lines.

A C-APDU has the following format:

<CLA> <INS> <P1> <P2> <LC> [<byte 0> <byte 1> ... <byte LC-1>] <LE> ;

where: <CLA> :: ISO 7816-4 class byte. <INS> :: ISO 7816-4 instruction byte. <P1> :: ISO 7816-4 P1 parameter byte. <P2> :: ISO 7816-4 P2 parameter byte. <LC> :: ISO 7816-4 input byte count. 1 byte <byte 0> ... <byte LC-1> :: input data bytes. <LE> :: ISO 7816- 4 expected output length. 1 byte

For this example we will use the com.licel.jcardsim.samples.HelloWorld Java Card Applet. It is a simple applet which processes the following APDU commands:

• Do nothing CLA=0x00 INS=0x02 P1=0x00 P2=0x00 LC=0x00
• Return bytes of "Hello world!" CLA=0x00 INS=0x01 P1=0x00 P2=0x00 LC=0x00
• Return sended data (echo) CLA=0x00 INS=0x01 P1=0x01 P2=0x00 LC=<length> DATA=<data>

Let's write a C-APDU script for our HelloWorld applet:

// CREATE APPLET CMD
0x80 0xb8 0x00 0x00 0x10 0x9 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x8 0x09 0x05 0x00 0x00 0x02 0xF 0xF 0x7f;
// SELECT APPLET CMD
0x00 0xa4 0x00 0x00 0x09 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x8 0x09 0x2;
// TEST NOP
0x00 0x02 0x00 0x00 0x00 0x2;
// test hello world from card
0x00 0x01 0x00 0x00 0x00 0x0d;
// test echo
0x00 0x01 0x01 0x00 0x0d 0x48 0x65 0x6c 0x6c 0x6f 0x20 0x77 0x6f 0x72 0x6c 0x64 0x20 0x21 0x0d;

Now we save the C-APDU script into the file helloworld.apdu and start the simulator. If we do not provide a third parameter the results will be printed on the console.

java -cp jcardsim-2.2.1-all.jar com.licel.jcardsim.utils.APDUScriptTool jcardsim.cfg helloworld.apdu

Result:

CLA: 80, INS: b8, P1: 00, P2: 00, Lc: 10, 09, 01, 02, 03, 04, 05, 06, 07, 08, 09, 05, 00, 00, 02, 0f, 0f, Le: 09, 01, 02, 03, 04, 05, 06, 07, 08, 09, SW1: 90, SW2: 00
CLA: 00, INS: a4, P1: 00, P2: 00, Lc: 09, 01, 02, 03, 04, 05, 06, 07, 08, 09, Le: 00, SW1: 90, SW2: 00
CLA: 00, INS: 02, P1: 00, P2: 00, Lc: 00, Le: 00, SW1: 90, SW2: 00
CLA: 00, INS: 01, P1: 00, P2: 00, Lc: 00, Le: 0d, 48, 65, 6c, 6c, 6f, 20, 77, 6f, 72, 6c, 64, 20, 21, SW1: 90, SW2: 00
CLA: 00, INS: 01, P1: 01, P2: 00, Lc: 0d, 48, 65, 6c, 6c, 6f, 20, 77, 6f, 72, 6c, 64, 20, 21, Le: 0d, 48, 65, 6c, 6c, 6f, 20, 77, 6f, 72, 6c, 64, 20, 21, SW1: 90, SW2: 00

The output matches the format used by apdutool.

Using BixVReaderCard

See the blog post: Work with jCardSim through PC/SC virtual reader