connect DB2 with Java

Please do try using

Class.forName("com.ibm.db2.jcc.DB2Driver");

This link might help: PUBLIB

You need to correct the package name.

Class.forName("com.ibm.db2.jdbc.app.DB2Driver");

To add .jar in your project, use menu Project → Properties → Java Build Path → tab Select "Libraries" → Add External Jars...