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jCardSim (Official repo of the jCardSim project)

Congratulations! jCardSim has won Duke's Choice 2013 Award!

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Please note that we moved our code repository from Google Code to GitHub.

jCardSim is an open source simulator for Java Card, v3.0.5:

  • javacard.framework.*
  • javacardx.crypto.*

Key Features:

  • Rapid application prototyping
  • Simplifies unit testing (5 lines of code)
// 1. create simulator
CardSimulator simulator = new CardSimulator();

// 2. install applet
AID appletAID = AIDUtil.create("F000000001");
simulator.installApplet(appletAID, HelloWorldApplet.class);

// 3. select applet

// 4. send APDU
CommandAPDU commandAPDU = new CommandAPDU(0x00, 0x01, 0x00, 0x00);
ResponseAPDU response = simulator.transmitCommand(commandAPDU);

// 5. check response
assertEquals(0x9000, response.getSW());
  • Emulation of Java Card Terminal, ability to use javax.smartcardio
  • APDU scripting (scripts are compatible with apdutool from Java Card Development Kit)
  • Simplifies verification tests creation (Common Criteria)


(Javadoc rendered:

Latest release 3.0.5:

What is the difference from Oracle Java Card Development Kit simulator?

  • Implementation of*

    One of the main differences is the implementation of*: the current version is analogous to an NXP JCOP 31/36k card. For example, in jCardSim we have support for on-card KeyPair.ALG_EC_F2M/ALG_RSA_CRT key generation. Oracle's simulator only supports KeyPair.ALG_RSA and KeyPair.ALG_EC_FP, which are not supported by real cards.

  • Execution of Java Card applications without converting into CAP

    jCardSim can work with class files without any conversions. This allows us to simplify and accelerate the development and writing of unit tests.

  • Simulator API

    jCardSim has a simple and usable API, which also allows you to work with the simulator using javax.smartcardio.*.

  • Cross-platform

    jCardSim is completely written in Java and can therefore be used on all platforms which support Java (Windows, Linux, MacOS, etc).

How to help jCardSim?

  • Join the team of jCardSim developers.
  • Try out DexProtector. The product is designed for strong and robust protection of Android applications against reverse engineering and modification.
  • Licel has one more product you may be interested in - Stringer Java Obfuscator. This tool provides all the features you need to comprehensively protect your Java applications.

License: Apache License 2.0

Third-party libraries: Legion of the Bouncy Castle Java

Trademarks: Oracle, Java and Java Card are trademarks of Oracle Corporation.