Inherits From:
NSObject
Inherits From:
com.apple.yellow.webobjects
Class Description
An EOAdaptorOperation object represents a primitive operation in a database server-lock, insert, update, or delete a row; or execute a stored procedure-and all the necessary information required by the operation. An EOAdaptorOperation is processed by an EOAdaptorChannel object in the method performAdaptorOperation
. You don't ordinarily create instances of EOAdaptorOperation; rather, the Framework automatically creates an EOAdaptorOperation object and sends it to an adaptor channel when your application needs the database server to perform an operation. You generally interact with EOAdaptorOperation objects only if you need to specify the order in which a set of operations are carried out (see the description for the EODatabaseContext delegate method databaseContext:willOrderAdaptorOperationsFromDatabaseOperations: ).
An EOAdaptorOperation has an entity and an operator (the type of operation the object represents). An adaptor operation's operator (AdaptorLockOperator, AdaptorInsertOperator, AdaptorUpdateOperator, AdaptorDeleteOperator, or AdaptorStoredProcedureOperator) determines additional, operator-dependent information used by the EOAdaptorOperation object. For example, only a stored procedure operation has an EOStoredProcedure object. The operator-dependent information is accessible using the methods described below.
EOAdaptorOperation
()
public EOAdaptorOperation
(Entity entity)
Creates and returns a new EOAdaptorOperation, with entity as the entity to which the operation will be applied.
See also:
entity
Instance Methods
adaptorOperator
public int adaptorOperator
Returns the receiver's adaptor operator. The operator indicates which of the other adaptor operation attributes are valid. For example, an adaptor operation whose operator is AdaptorInsertOperator uses changedValues
, but not attributes
, qualifier
, or storedProcedure
.
See also:
setAdaptorOperator
attributes
public NSArray attributes
()
Returns the array of attributes to select when locking the row. If attributes have not been assigned to the receiver, the primary key attributes are selected. Only valid for adaptor operations with the AdaptorLockOperator.
See also:
setAttributes
changedValues
public NSDictionary changedValues
()
Returns the dictionary of values that need to be updated, inserted, or compared for locking purposes.
See also:
setChangedValues
compareAdaptorOperation
public int compareAdaptorOperation
(EOAdaptorOperation anAdaptorOperation)
Orders adaptor operations alphabetically by entity name and by adaptor operator within the same entity. The adaptor operators are ordered as follows:
An EODatabaseContext uses compareAdaptorOperation:
to order adaptor operations before invoking EOAdaptorChannel's performAdaptorOperations
method.
entity
public EOEntity entity
()
Returns the entity to which the operation will be applied.
See also: "Constructors"
exception
public java.lang.Throwable exception
()
Returns the exception that was thrown when an adaptor channel attempted to process the receiver. Returns null
if no exception was thrown or if the receiver hasn't been processed yet.
See also:
setException
qualifier
public com.apple.yellow.eocontrol.EOQualifier qualifier
()
Returns the qualifier that identifies the specific row to which the operation applies. Not valid with adaptor operations with the operators AdaptorInsertOperator and AdaptorStoredProcedureOperator.
See also:
setStoredProcedure
setAdaptorOperator
public void setAdaptorOperator
(int adaptorOperator)
Sets the receiver's operator to adaptorOperator, which is one of the following:
See also:
adaptorOperator
setAttributes
public void setAttributes
(NSArray attributes)
Sets the array of attributes to select when locking the row. The selected values are compared in memory to the corresponding snapshot values to determine if a row has changed since the application last fetched it. attributes is an array of EOAttribute objects that can't be compared in a qualifier (generally BLOB types); it should not be null
or empty. Generally, an adaptor operation's qualifier contains all the comparisons needed to verify that a row hasn't changed since the application last fetched, inserted, or updated it. In this case (if there aren't any attributes that can't be compared in a qualifier), attributes should contain primary key attributes. This method is only valid for adaptor operations with the AdaptorLockOperator.
See also:
attributes
, entity
setChangedValues
public void setChangedValues
(NSDictionary changedValues)
Sets the dictionary of values that need to be updated, inserted, or compared for locking purposes. changedValues is a dictionary object whose keys are attribute names and whose values are the values for those attributes. As summarized in the following table, the contents of changedValues depends on the receiver's operator:
Operator | Contents of changedValues Dictionary |
---|---|
AdaptorLockOperator | snapshot values used to verify that the database row hasn't changed since this application last fetched it |
AdaptorInsertOperator | the values to insert |
AdaptorUpdateOperator | the new values for the columns to update |
AdaptorDeleteOperator | snapshot values (changedValues is only valid for AdaptorDeleteOperation if the receiver's entity uses a stored procedure to perform delete operations.) |
AdaptorStoredProcedureOperator | snapshot values |
See also:
changedValues
setException
public void setException
(java.lang.Throwable exception)
Sets the receiver's exception to exception. This method is typically invoked from EOAdaptorChannel's performAdaptorOperations
method. If a database error occurs while processing an adaptor operation, the adaptor channel creates an exception and assigns it to the adaptor operation.
See also:
exception
setQualifier
public void setQualifier
(com.apple.yellow.eocontrol.EOQualifier qualifier)
Sets the qualifier that identifies the row to which the adaptor operation is to be applied to qualifier.
See also:
qualifier
setStoredProcedure
public void setStoredProcedure
(EOStoredProcedure storedProcedure)
Sets the receiver's stored procedure to storedProcedure.
See also:
storedProcedure
storedProcedure
public EOStoredProcedure storedProcedure
()
Returns the receiver's stored procedure. Only valid with adaptor operations with the AdaptorStoredProcedureOperation.
See also:
setStoredProcedure