Methods of specifying Jython settings

• preProperties, typically Java system properties specified with -D before class/jar specification on Java command line

• Registry: property files registry in Jython root and .jython in user.home; if both are present, the latter replaces the former completely. If either is present, the Java system properties are replaced entirely. (This is likely a bug in PySystemState.addRegistryFile.) See Finding the Registry File for more information.

• postProperties, typically Jython properties specified with -D after class/jar specification on Java command line (these overwrite Java system properties, too.)

For preProperties and postProperties, alternate properties may be passed to PySystemState.initialize or PythonInterpreter.initialize by programmatic users of Jython.

The runtime registry (PySystemState.registry from Java, or sys.registry from Python) is created from the above three sources.

Other command-line arguments are written directly into Options static variables without going through the properties system; the overlapping properties are python.divisionWarning, python.options.Qnew and python.verbose. In these overlapping cases, the above three sources always take precedence over the command-line equivalents. (This precedence should likely be reversed.)

Documentation

• The options whose destinations are static variables in the Options class are well-documented there.

• The default registry file is severely bitrotted and needs redoing.

• The Jython user guide refers to a subset of these properties.