As you have learned over the past 2 days, CMP saves a lot of development time when you have to develop simple applications. For complex data access, CMP still has a few limitations. In addition, though the EJB QL has been introduced in EJB 2.0, it does not provide the full-fledged querying capabilities that you would expect from a query language. Hence, CMP is recommended for applications that do not have complex database table relations.
BMP, on the other hand, has a longer development curve, since the persistence code has to be hand-coded by the bean provider. The advantage of BMP is that it enables developers to have the necessary flexibility to write complex SQL queries for accessing data. Hence, if you need to migrate to EJB any existing Java applications that use JDBC, while keeping the existing code intact as far as possible, then BMP is the less risky solution for you.
Q2:
Does WebLogic Server support Java Data Objects?
A2:
Java Data Objects is a fairly new standard, and there is a lot of debate over its use and adoption, since EJB already has a persistence framework defined. Hence, you will have to wait for general acceptance of Java Data Objects before WebLogic Server supports the standard. Remember, BEA is well known for delivering robust products that conform to standards accepted and supported in the industry.
