OracleAS TopLink Exceptions

Runtime Exceptions

Runtime exceptions indicate error conditions at runtime, though not necessarily fatal errors. Instead, they indicate that runtime conditions are invalid, such as the loss of a database connection. All these exceptions must be handled in a try-catch block.

The following exceptions can be thrown at runtime:

• DatabaseException

• OptimisticLockException

• CommunicationException

Development Exceptions

Development exceptions indicate that a certain fragment of code is invalid. All development exceptions do not depend on runtime conditions and must, therefore, be solved before deploying the application. For example, the DescriptorException is thrown the first time you initialize an application that contains an erroneous descriptor or mapping property. Development exceptions are useful as a debugging tool to find inconsistencies in the descriptor. Because development exceptions represent abnormal behavior, they must not be handled in a try-catch block.

The following exceptions are not dependent on runtime conditions. If one of these exceptions is thrown, then the application code being tested is invalid and must be changed. Avoid handling these types of exceptions:

• DescriptorException

• BuilderException

• ConcurrencyException

• ConversionException

• QueryException

• ValidationException

Format of Exceptions

All exceptions return the name of the exception and a message that describes what caused the exception. The message that appears reflects the type of exception.

OracleAS TopLink exceptions include the following information:

• The name of the OracleAS TopLink exception

• A description of the most probable cause of the error

• A native error code

Exception Error Code Numbers

OracleAS TopLink does not necessarily use the full range of exception error code numbers available. Table C-1 indicates the potential range: