What JDBC drivers does IBM provide for the OS/400 database?
IBM provides two different JDBC drivers for the OS/400 database:

The "Native" JDBC driver. This is shipped as part of the AS/400 Developer Kit for Java (57xxJV1). It is implemented by making native method calls to the SQL CLI (Call Level Interface). Consequently, it only runs on the OS/400 JVM. The class name to register is com.ibm.db2.jdbc.app.DB2Driver . The URL subprotocol is db2 .
The "Toolbox" JDBC driver. This is shipped as part of the IBM Toolbox for Java (57xxJC1). It is implemented by making direct socket connections to the database host server. This happens to be the same route that the Client Access/400 ODBC driver takes. However, Client Access/400 is NOT required. The Toolbox runs on any JVM. The class name to register is com.ibm.as400.access.AS400JDBCDriver . The URL subprotocol is as400 .