Debugging Jython

The Jython debugger module is called pdb. (The 'p' in 'pdb' stands for Python — Jython is just a Java port of Python). The pdb module lets you debug Jython scripts, line-by-line.

To run a script in debug mode, import the pdb module and insert the set_trace() function call near the beginning of the script or where you suspect problems:

Run the script from the CLI. The script will pause, expecting input, when it reaches the pdb.set_trace() line in the script's execution. You can use the following commands to navigate the debugger.

Command	Description
n	Executes the next line of the script.
l	Lists 10 lines of script above and 10 lines below the current position.
s	Steps into the function in the next line of the script.
b line_number	Sets a break point at the specified line number.
c	Continues execution uninterrupted until the next break point.
r	Continues executing the function in current scope until it returns.
p variable	Print the value of the variable in the current scope.