Debugging the HelloWorld Sample from the Command Line To debug the HelloWorld sample from the command line: Open a terminal window and perform the following: Navigate to the JC_HOME_SIMULATOR/runtime/bin directory. Start the simulator by entering the following command at the command prompt: [jcsw.exe|./jcsl] -debug_port=9090 Open a second terminal window and perform the following: Navigate to the JC_HOME_SIMULATOR/samples/HelloWorld directory. Edit AMSHelloWorldClient.java to send only the deploy script. Execute the build script: [build.bat|./build.sh] This builds the applet and the client. Execute the run script: [run.bat|./run.sh] This will deploy the applet. In the second command prompt, navigate to the JC_HOME_SIMULATOR/client/DebugProxy directory and start the debug proxy: java -jar jc-debug-proxy.jar -capPath ${JC_HOME_SIMULATOR}/samples/HelloWorld/applet/deliverables/HelloWorld/com/oracle/jcclassic/samples/helloworld/javacard/helloworld.cap Start the Java debugger of your choice and attach it to the 8000 port of the local host. Now you can set a break point and see it hit after a proper APDU is issued using the AMService API.