Source Level Debugging

You can debug applications running on NetWare using any JDPA compliant debugger or debugging IDE. The following are available debuggers:

• NetBeans (www.NetBeans.org)
• Forte (forte.sun.com)
• Novell's Silverstream IDE

Remote and local debugging of Java Applications are available through the socket transport.

IMPORTANT:  The socket transport name of NetWare is dt_skt. On other platforms, it is dt_socket.

Required VM Options

To debug applications, you need the following debug invocation options:

• -Xdebug. Enables debugging.
• -Xrunjdwp: <sub_options> Loads the JPDA reference implementation of JDWP. This library resides in the target VM and uses JVMDI and JNI to interact with it. It uses a transport and the JDWP protocol to communicate with a separate debugger application. The following section describes the specific sub_options:

  Name	Required	Default Value	Description
  Help	No	N/A	Prints a brief help message and exits the VM.
  Transport	Yes	none. Must be dt_skt	Name of the transport to use in connecting to debugger application
  Server	No	N	If Y, listen for a debugger application to attach; otherwise attach to the debugger application at the specified address If Y and no address is specified, choose a transport address to listen to a debugger application at and print the address to the standard output stream.
  Address	Yes, if server = n; otherwise, no		Transport address for the connection. If server=n, attempt to attach to debugger application at this address. If server=y, listen for a connection at this address.

-Xrunjdwp Examples

-Xrunjdwp:transport=dt_skt,server=y,address=8000

Listen for a socket connection on port 8000. Suspend this VM before main class loads (suspend=y by default). After the debugger application connects, it can resume the VM.

-Xrunjd2p:transport=dt_skt,address=8000

Start the application without suspending. Then listen for a socket connection on port 8000. When the debugger application connects, it can suspend the VM.

Complete Examples

java -Xdebug  
-runjdwp:transport=dt_skt,server=y,address=8000 
-Xbootclasspath/a:SYS:/myapp/foo.jar HelloWorld

Listen for a socket connection on port 8000. Suspend this VM before the main class loads. After the debugger application connects, it can send a JDWP command to resume the VM of the HelloWorld application.