14.22 Standard Exceptions

This section presents the standard exceptions defined for the ORB. These exception identifiers may be returned as a result of any operation invocation, regardless of the interface specification. Standard exceptions are not listed in raises expressions.

To bound the complexity in handling the standard exceptions, the set of standard exceptions is kept to a tractable size. This constraint forces the definition of equivalence classes of exceptions, rather than enumerating many similar exceptions.

For example, an operation invocation can fail at many different points due to the inability to allocate dynamic memory. Rather than enumerate several different exceptions that correspond to the different ways that memory allocation failure causes the exception (during marshaling, unmarshaling, in the client, in the object implementation, allocating network packets, and so forth), a single exception corresponding to dynamic memory allocation failure is defined. Each standard exception includes a minor code to designate the subcategory of the exception; the assignment of values to the minor codes is left to each ORB implementation.

Each standard exception also includes a completion_status code, which takes one of the following values:

CORBA::COMPLETED_YES

The object implementation completed processing prior to the exception being raised.

CORBA::COMPLETED_NO

The object implementation was not initiated prior to the exception being raised.

CORBA::COMPLETED_MAYBE

The status of implementation completion is unknown.

• Exception Definitions
  
• Object Nonexistence
  
• Transaction Exceptions