Encapsulates the error state of an object or operation. More...

#include <rw/db/status.h>

Inherits RWDBFuture.

Public Types
enum	ErrorCode { ok , noMem , notInitialized , typeConversion , dbNotFound , serverError , serverMessage , vendorLib , notConnected , endOfFetch , invalidUsage , columnNotFound , invalidPosition , notSupported , nullReference , notFound , missing , noMultiReaders , noDeleter , noInserter , noUpdater , noReader , noIndex , noDrop , wrongConnection , noPrivilege , noCursor , cantOpen , applicationError , notReady , internalError , cacheWriteError , cacheReadError }

typedef void(*	ErrorHandler) (const RWDBStatus &status)

Public Member Functions
	RWDBStatus ()

	RWDBStatus (const RWDBStatus &status)

ErrorCode	errorCode () const

ErrorHandler	errorHandler () const

bool	isTerminal () const

bool	isValid () const

RWCString	message () const

RWDBStatus &	operator= (const RWDBStatus &status)

void	raise () const

void	setErrorHandler (ErrorHandler handler)

long	vendorError1 () const

long	vendorError2 () const

RWCString	vendorMessage1 () const

RWCString	vendorMessage2 () const

Detailed Description

RWDBStatus encapsulates the error state of an object or operation. A valid object or a successful operation is represented by RWDBStatus::ok. An RWDBStatus that is not valid contains an error code, an error message, and often some supplemental information provided by a database vendor's API.

Each RWDBStatus object contains a callback routine that can be changed by an application. If an RWDBStatus changes state to anything but RWDBStatus::ok, the installed handler is called with self as an argument.

In the error model of the DB Interface Module, the use of exceptions is optional, and is under the application's control. The raise() method of RWDBStatus throws an exception of type RWExternalErr. Thus, an application may choose to enforce a terminating or nonterminating model of error handling by installing an appropriate error handler.

When objects of the DB Interface Module are produced by other objects, the produced object's status is copied from the producer. Consequently, an application can control error handling at any level it chooses. A handler installed in the RWDBManager is propagated to every object of The DB Interface Module in the application; one installed in an RWDBDatabase is propagated to each object produced by that RWDBDatabase, and so on down to the level of individual objects.

RWDBStatus is designed around the Interface/Implementation paradigm. An RWDBStatus instance is an interface to a reference-counted implementation; copy constructors and assignment operators produce additional references to a shared implementation.

Synopsis: #include <rw/db/status.h>

RWDBStatus status = myDbase.status(); //status of object

RWDBStatus status =

myDbase.createTable("tableName", myschema); //status of function

RWDBStatus
Encapsulates the error state of an object or operation.
Definition status.h:80

Example: An application that requires C++ exceptions throughout would proceed this way:

void throwStatus(const RWDBStatus& status) { status.raise(); }

RWDBManager::setErrorHandler(throwStatus);

RWDBManager::setErrorHandler
static RWDBStatus::ErrorHandler setErrorHandler(RWDBStatus::ErrorHandler handler)

RWDBStatus::raise
void raise() const

Member Typedef Documentation

◆ ErrorHandler

typedef void(* RWDBStatus::ErrorHandler) (const RWDBStatus &status)

A typedef for the error handling function.

Member Enumeration Documentation

◆ ErrorCode

enum RWDBStatus::ErrorCode

Possible RWDBStatus error codes.

Enumerator
ok	No error
noMem	Out of Memory
notInitialized	Object never initialized
typeConversion	Type conversion error
dbNotFound	Database not registered
serverError	Error reported by server
serverMessage	Message from server
vendorLib	Error in vendor's library
notConnected	Lost connection
endOfFetch	End of fetch
invalidUsage	Invalid usage of object
columnNotFound	Column does not exist
invalidPosition	Invalid positioning within object, i.e. bounds error
notSupported	Unsupported feature
nullReference	Null reference parameter
notFound	Database object not found
missing	Required piece of information is missing
noMultiReaders	This object cannot support multiple readers
noDeleter	This object cannot support deletions
noInserter	This object cannot support insertions
noUpdater	This object cannot support updates
noReader	This object cannot support readers
noIndex	This object cannot support indices
noDrop	This object cannot be dropped
wrongConnection	Incorrect connection was supplied
noPrivilege	This object cannot support privileges
noCursor	This object cannot support cursors
cantOpen	Unable to open
applicationError	For errors produced at the application level
notReady	For future use
internalError	Error in the SourcePro library
cacheWriteError	Error writing to the cache.
cacheReadError	Error reading from the cache.

Constructor & Destructor Documentation

◆ RWDBStatus() [1/2]

RWDBStatus::RWDBStatus ( )

The default constructor creates an RWDBStatus of notInitialized. Data members are set to default values of 0 or the empty string, and the error handler is set to rwnil.

◆ RWDBStatus() [2/2]

RWDBStatus::RWDBStatus ( const RWDBStatus & status )

Copy constructor. The created RWDBStatus shares an implementation with status.

Member Function Documentation

◆ errorCode()

ErrorCode RWDBStatus::errorCode ( ) const

Returns self's error code. The code errorCode() != ok can be interpreted as an abnormal condition.

◆ errorHandler()

ErrorHandler RWDBStatus::errorHandler ( ) const

Returns self's installed error handler, if any.

◆ isTerminal()

bool RWDBStatus::isTerminal ( ) const

Returns true if the error that occurred will terminate the application.

◆ isValid()

bool RWDBStatus::isValid ( ) const

Returns true if errorCode() == ok, otherwise returns false.

◆ message()

RWCString RWDBStatus::message ( ) const

Returns the error message associated with the current error code. Returns an empty string if the current error code is ok.

◆ operator=()

RWDBStatus & RWDBStatus::operator= ( const RWDBStatus & status )

Assignment operator. Self shares an implementation with status. Returns a reference to self.

◆ raise()

void RWDBStatus::raise ( ) const

Throws an exception that contains the error message associated with self.

◆ setErrorHandler()

void RWDBStatus::setErrorHandler ( ErrorHandler handler )

Installs handler as self's error handler. The supplied handler is inherited by all objects produced by self. By default, an RWDBStatus::ErrorHandler is inherited from the object that produced it; this method overrides the default.

◆ vendorError1()

long RWDBStatus::vendorError1 ( ) const

Returns a code supplied by the database vendor, or 0 if not relevant.

◆ vendorError2()

long RWDBStatus::vendorError2 ( ) const