Is the SAP Java Connector still a good way to connect a Java Application with SAP ? Will there be a support and maintenance of the connector in the future (especially in ECC 6.0) or is the one and only good way the usage of the "Enterprise Services" in ECC 6.0 ?
Considering that the Java Connector was only recently re-developed to version 3 and is now used to bridge the gap between the NetWeaver Java Stack and its ABAP counterpart, it's safe to assume the JCo will be around for quite some time. I'd always prefer using the JCo to Web Services if I have the choice - less overhead, easier on the ABAP side. You might want to take a look at tools like HiberSAP, RCER or sap4j to make life a little easier on the Java side - that is, reducing the amount of boilerplate code and focusing on the really important things.