Find Message in WD java

Dear Team,

In ESS, we are facing one issue while declaring Income tax declaration.

The message is error while maintaining the infotype 0002.

How i come to know, why this message is coming. Does this message defined in WD ABAP or how i can debug this.

I found the message class in SAP but there is no where to use of the message class.

Thanks and Regards,

Nishant Bansal.