Connection to DB2 using jaydebeapi not working

Question

I need to create a connection to a DB2 database in an IBM i system, using Python library jaydebeapi, with the following instruction:

import sys
import jaydebeapi
import os

try:
    conn = jaydebeapi.connect("com.ibm.as400.access.AS400JDBCDriver",
        f"jdbc:as400://{hostname};naming=system;libraries=*LIBL;errors=full;date format=iso;time format=iso;translate binary=true;data truncation=false",
        [user, password],
        f"{dirname}\jt400-20.0.0.jar")
except jaydebeapi.Error as e:
    print(f"Error connecting to DB2 Platform: {e}")
    sys.exit(1)
print(f"Connection to DB2 was successful")

The script ends with no errors, but it prints nothing on console. Debugging the script I found the instruction that does nothing is the following:

_jpype.startup(jvmpath, tuple(args), ignoreUnrecognized, convertStrings, interrupt)

This instruction is in the _core.py module within jpype library.

Debugging the script with pdb shows the following:

(.venv) C:\scripts>python carga.py

jvmpath: C:\Program Files\Java\jdk1.8.0_121\jre\bin\server\jvm.dll, tuple(args): ('-Djava.class.path=C:\\scripts\\jt400-20.0.0.jar',)

> C:\scripts\.venv\lib\site-packages\jpype\_core.py(227)startJVM()

-> _jpype.startup(jvmpath, tuple(args), ignoreUnrecognized, convertStrings, interrupt)

(Pdb) s

(.venv) C:\scripts>

And that’s it, no error, no message, nothing.

I was unable to find startup function in any of the libraries I have installed.

I checked that the class com.ibm.as400.access.AS400JDBCDriver is contained within the given jar jt400-20.0.0.jar:

enter image description here

I’m using Python 3.11.4 win-64, and java 1.8.0_121 win-64

Answer 1

The problem seems related to the loading of java. But did you try with jt400-20.0.0-java8.jar ?

it is specifically for java 8.