net.sf.farrago.fennel
Interface FennelDbHandle

All Superinterfaces:

ClosableAllocation, FarragoAllocation

All Known Implementing Classes:

FennelDbHandleImpl

public interface FennelDbHandle
extends FarragoAllocation

FennelDbHandle is a public wrapper for FennelStorage, and represents a handle to a loaded Fennel database.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/fennel/FennelDbHandle.java#27 $

Author:

John V. Sichi, turned into an interface by Hunter Payne

Method Summary

FennelJavaHandle	allocateNewObjectHandle(FarragoAllocationOwner owner, Object obj) Creates a native handle for a Java object for reference by XML commands.
void	closeAllocation() Closes this object.
long	executeCmd(FemCmd cmd) Executes a FemCmd object.
long	executeCmd(FemCmd cmd, FennelExecutionHandle execHandle) Executes a FemCmd object, associating an optional execution handle with the command.
String	getAccessorXmiForTupleDescriptorTraced(FemTupleDescriptor tupleDesc) Constructs a FemTupleAccessor for a FemTupleDescriptor.
FemDbHandle	getFemDbHandle(FarragoMetadataFactory callerFactory)
FarragoMetadataFactory	getMetadataFactory()
EigenbaseException	handleNativeException(SQLException ex)
void	setObjectHandle(long handle, Object obj) Changes the object referenced by a handle.

Method Detail

getMetadataFactory

FarragoMetadataFactory getMetadataFactory()

getFemDbHandle

FemDbHandle getFemDbHandle(FarragoMetadataFactory callerFactory)

Parameters:

callerFactory - override for metadataFactory

Returns:

FemDbHandle for this database

getAccessorXmiForTupleDescriptorTraced

String getAccessorXmiForTupleDescriptorTraced(FemTupleDescriptor tupleDesc)

Constructs a FemTupleAccessor for a FemTupleDescriptor. This shouldn't be called directly except from FennelRelUtil.

Parameters:

tupleDesc - source FemTupleDescriptor

Returns:

XMI string representation of FemTupleAccessor

executeCmd

long executeCmd(FemCmd cmd)

Executes a FemCmd object. If the command produces a resultHandle, it will be set after successful execution.

Parameters:

cmd - instance of FemCmd with all parameters set

Returns:

return handle as primitive

executeCmd

long executeCmd(FemCmd cmd,
                FennelExecutionHandle execHandle)

Executes a FemCmd object, associating an optional execution handle with the command. If the command produces a resultHandle, it will be set after successful execution.

Parameters:

cmd - instance of FemCmd with all parameters set

execHandle - the execution handle associated with the command; null if there is no associated execution handle

Returns:

return handle as primitive

allocateNewObjectHandle

FennelJavaHandle allocateNewObjectHandle(FarragoAllocationOwner owner,
                                         Object obj)

Creates a native handle for a Java object for reference by XML commands. After this, the Java object cannot be garbage collected until its owner explicitly calls closeAllocation.

Parameters:

owner - the object which will be made responsible for the handle's allocation as a result of this call

obj - object for which to create a handle, or null to create a placeholder handle

Returns:

native handle

setObjectHandle

void setObjectHandle(long handle,
                     Object obj)

Changes the object referenced by a handle.

Parameters:

handle - the handle to change

obj - new object

closeAllocation

void closeAllocation()

Description copied from interface: ClosableAllocation

Closes this object.

Specified by:

closeAllocation in interface ClosableAllocation

handleNativeException

EigenbaseException handleNativeException(SQLException ex)