JAVA mapping record list with conditions

Hello dear all,

I am new here and in WM also. I have an issue:

i need to write a java service that takes a record list with conditions and maps it to another record list. An input record list may have subrecords.

input: multilevel recordlist, condition (variable=value)
output: recordlist (the same structure as the input one)

Thank you in advance,
Vassili