com.mckoi.database
Interface DatabaseProcedure

public interface DatabaseProcedure

This interface represents a database procedure that is executed on the server side. It is used to perform database specific functions that can only be performed on the server.

A procedure must manage its own table locking.

Author:

Tobias Downer

Method Summary

Table	execute(User user, java.lang.Object[] args) Executes the procudure and returns the resultant table.
int	getLockingMode() Returns the locking mode in which the database operates.
DataTable[]	getReadTables(DatabaseConnection db) This returns a DataTable[] array that lists the DataTables that are read during this procedure.
DataTable[]	getWriteTables(DatabaseConnection db) Returns a DataTable[] array that lists the DataTables that are written to during this procedure.
void	setLockHandle(LockHandle lock_handle) Sets the LockHandle object for this procedure.

Method Detail

execute

Table execute(User user,
              java.lang.Object[] args)
              throws DatabaseException

Executes the procudure and returns the resultant table. Note, the args have to be serializable. There may be only 0 to 16 arguments. The method may throw a 'DatabaseException' if the procedure failed.

Throws:

DatabaseException

getReadTables

DataTable[] getReadTables(DatabaseConnection db)
                          throws DatabaseException

This returns a DataTable[] array that lists the DataTables that are read during this procedure.

Throws:

DatabaseException

getWriteTables

DataTable[] getWriteTables(DatabaseConnection db)
                           throws DatabaseException

Returns a DataTable[] array that lists the DataTables that are written to during this procedure.

Throws:

DatabaseException

getLockingMode

int getLockingMode()

Returns the locking mode in which the database operates. This is either LockingMechanism.SHARED_MODE or LockingMechanism.EXCLUSIVE_MODE. In most cases this will be SHARED_MODE.

setLockHandle

void setLockHandle(LockHandle lock_handle)

Sets the LockHandle object for this procedure. This should be called after the tables that this procedure uses have been locked.