Exceptions
All exceptions in Storm inherit from the class core.Exception, which is a class-type. The
core.Exception-class is abstract, and expects derived classes to override the message(StrBuf)
function, which is to provide a custom message for the exception when printed.
Exceptions do not record a stack trace by default since this is a fairly expensive operation. The
core.Exception class contains a saveTrace function that records a stack trace into the exception
that will be printed by the default toS implementation. Many of the built-in exceptions in Storm
represent events that are fatal, and are thereby not expected to be caught and recovered from and
therefore collect stack-traces by default to aid debugging (in these cases the performance impact is
less important compared to debuggability). Therefore, classes inheriting from these classes do not
need to call saveTrace again.
Storm defines the following generic exception classes:
RuntimeError: Generic runtime errors originating from the runtime systemGcError: Exception thrown by the garbage collector. Typically due to allocation failures (i.e., out of memory).NumericError: Error in numerical operations.DivisionByZero: Thrown on division by zero. Note: can not necessarily be caught in C++.MemoryAccessError: Thrown on invalid memory accesses. Note: can not necessarily be caught in C++.
NotSupported: Thrown from interfaces where the requested operation is not supported.UsageError: Thrown on invalid usage of some part of the system.InternalError: Internal errors from the compiler or runtime system.StrError,MapError,SetError,ArrayError: Errors thrown by the standard containers if they are used incorrectly (e.g. accessing elements that don't exist).