Re: [Jython-users] Exception handling ...

[Kevin B. <kb...@ca...>]

> V=E1clav Tolar wrote:
>=20
> Hello,
> I would like to get help from you.
> I am using PythonInterpreter object to execute some Python commands=
. If executing command has bad syntax or throwing exception, some jav=
a exception from exec(String) method is thrown.
> Now, what I want to is to determine what KIND of error in python co=
mmad was occured - for example there is SYNTAX ERROR or PYTHON EXCEPT=
ION is thrown.

You can do this by grabbing sys.last_value and sys.last_type.

Example follows:

import org.python.util.*;
import org.python.core.*;
import java.io.*;
import java.util.*;

/**
 * Test for exception in executed code by looking at sys.last_value, =
etc.
 **/
public class InterpException
{
    public static void main( String[] args )
        throws Exception
    {
        PythonInterpreter.initialize(
            System.getProperties(),
            new Properties(),
            args
            );
                                     =20
        InteractiveInterpreter interp =3D new InteractiveInterpreter(=
); //#Console(); //#
        String inputLine =3D "";
        String taskText =3D "";
        DataInputStream in =3D new DataInputStream( System.in );
        boolean more;
        String prompt =3D ">>>";

        // get 'sys' imported
        interp.runsource( "import sys" );

        // get reference to 'sys' module
        PyString sysName =3D new PyString( "sys" );
        PyStringMap locals =3D (PyStringMap) interp.getLocals();
        PySystemState sys =3D (PySystemState) locals.get( sysName );

        PyObject lastValue;
       =20
        System.out.print( prompt );
        while ((inputLine =3D in.readLine()) !=3D null){
            lastValue =3D sys.last_value; // sentinel to check if it =
hasn't changed
            if ( taskText.length() > 0 )
            {
                taskText +=3D "\n";
            }
            taskText +=3D inputLine;
            more =3D interp.runsource( taskText );
            if ( more )
            {
                prompt =3D "...";
            }
            else
            {
                taskText =3D "";
                prompt =3D ">>>";
            }

            if ( lastValue !=3D sys.last_value ) // an error occurred=
 in this statement
            {
                System.out.println( "An error of type: " + sys.last_t=
ype + " occurred." );
                // use sys.last_traceback and sys.last_value as desir=
ed...
            }
           =20
            System.out.print( prompt );
        }
    }
}


kb