Hi Victor,
If you have <SCA file> (Software component Archive) in which your Java and WD Java <EAR files> (development components) are packed, then you can import the SCA in your NWDS and create the local DCs.
Please follow the below document for the same:
How to Import the Web Dynpro Demo Components SCA File into NetWeaver Developer Studio
If you do not have the SCA file, then you may be interested to unzip the ear files and decompile the class files to look for the code for the reference and re-create the DC again in your NWDS with the required code.
BR,
Anurag