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Container-managed data access support
Complex types:
Any class implementing java.io.Serializable, such as Vector and
Hashtable
Other entity bean references
Note
The Borland CMP engine now supports using the Long value type for dates, as well as
java.sql.Date for java.util.Date.
Keep in mind that the Borland Container supports classes implementing the
java.io.Serializable interface, such as Hashtable and Vector. The container supports
other data types, such as Java collections or third party collections, because they also
implement java.io.Serializable. For classes and data types that implement the
Serializable interface, the Container merely serializes their state and stores the result
into a BLOB. The Container does not do any “smart” mapping on these classes or types;
it just stores the state in binary format. The Container's CMP engine observes the
following rule: the engine serializes as a BLOB all types that are not one of the explicitly
supported types.
Depending on your database implementation, the following data types require fetching
based on column index:
Database
Data Types
Oracle ■ LONG RAW
Sybase ■ NTEXT
■
IMAGE
MS SQL ■ NTEXT
■
IMAGE
Note
If you use either of the two data types BINARY (MS SQL) or RAW (Oracle) as primary keys,
you must explicitly specify their size.
Support for Oracle Large Objects (LOBs)
There are two types of Large Objects (LOBs), Binary Large Objects (BLOBs) and
Character Large Objects (CLOBs).
BLOBs are mapped to CMP fields with the following data types:
■
byte[]
■
java.io.Serializable
■
java.io.InputStream
CLOBs, by virtue of being Character Large Objects, can only be mapped to cmp-fields
with the java.lang.String data type.
160 BES Developer’s Guide