Using a lookup for mapping program to retrieve the specific value

Hi All,

I have a scenario like …I need to use a lookup for mapping program to retrieve the specific value based on the input parameters.

Here I have got some rough idea like …

1. Creation of java program to connect the DB table and access the values, Import this java program as archive into XI.

2. Creation of user defined function to use the above java program

3. Include the user defined function in the interface mapping.

Here I feel it needs some more info to complete this scenario, so can anyone provide the step by step procedure for the above scenario.

Thanks in advance.

Vijay.