Top Description Fields Constructors Methods
org.apache.derby.impl.store.raw.data

public final Class LogicalUndoOperation

extends PageBasicOperation
implements Compensation
Class Inheritance
All Implemented Interfaces
org.apache.derby.iapi.store.raw.Compensation, org.apache.derby.iapi.store.raw.Loggable, org.apache.derby.iapi.services.io.Formatable, org.apache.derby.iapi.services.io.TypedFormat, java.io.Externalizable, java.io.Serializable
Imports
org.apache.derby.iapi.services.io.StoredFormatIds, .CompressedNumber, .LimitObjectInput, org.apache.derby.shared.common.sanity.SanityManager, org.apache.derby.iapi.store.raw.Compensation, .Loggable, .Transaction, .Undoable, org.apache.derby.iapi.store.raw.log.LogInstant, org.apache.derby.shared.common.error.StandardException, org.apache.derby.iapi.util.ByteArray, java.io.ObjectOutput, .ObjectInput, .IOException
LogicalUndoOperation is a compensation operation that rolls back the change of an LogicalUndoable operation. A LogicalUndoOperation itself is not undo-able, i.e, it is loggable but not undoable. 





Field Summary




Modifier and TypeField and Description

protected int
recordId




private transient LogicalPageOperation
undoOp
The operation to be rolled back







Inherited from org.apache.derby.impl.store.raw.data.PageBasicOperation:


containerHdlfoundHerepage







Constructor Summary




AccessConstructor and Description

pack-priv
LogicalUndoOperation(BasePage page)




pack-priv
LogicalUndoOperation(BasePage page, int recordId, LogicalPageOperation op)
Set up a compensation operation during run time rollback



public
LogicalUndoOperation()
Return my format identifier.









Method Summary




Modifier and TypeMethod and Description

public final void
doMe(Transaction 
the Transaction that is doing the rollback
xact, LogInstant 
the log instant of this undo operation
instant, LimitObjectInput 
optional data
in)
Implements org.apache.derby.iapi.store.raw.Loggable.doMe.


Apply the undo operation, in this implementation of the
RawStore, it can only call the undoMe method of undoOp



public final ByteArray
getPreparedLog()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.getPreparedLog.


Implements org.apache.derby.iapi.store.raw.Loggable.getPreparedLog.


The log operations are responsible to create the ByteArray, and the log
		operations should write out any optional data for the change to the 
        ByteArray.



public int
getTypeFormatId()
Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.


Get a universally unique identifier for the type of
this object.



public int
group()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.group.


Implements org.apache.derby.iapi.store.raw.Loggable.group.


Get the loggable's group value



public void
readExternal(ObjectInput 
the stream to read data from in order to restore the object
in)
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.readExternal.


Implements java.io.Externalizable.readExternal.


Read this in



public void
releaseResource(Transaction xact)
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.releaseResource.


Implements org.apache.derby.iapi.store.raw.Loggable.releaseResource.


Release any resource that was acquired for doMe for rollback or
recovery redo.



public void
restoreMe(Transaction 
the Transaction doing the rollback
xact, BasePage 
the page to rollback changes on
undoPage, LogInstant 
the log instant of this (PageUndo) operation
CLRinstant, LimitObjectInput 
optional data for the rollback operation
in)
Implements abstract org.apache.derby.impl.store.raw.data.PageBasicOperation.restoreMe.


Undo the change indicated by this log operation and optional data.



public void
setUndoOp(Undoable 
the Undoable operation
op)
Implements org.apache.derby.iapi.store.raw.Compensation.setUndoOp.


Set up a LogicalOperation during recovery redo.



public String
toString()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.toString.


DEBUG: Print self.



public void
writeExternal(ObjectOutput 
the stream to write the object to
out)
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.writeExternal.


Implements java.io.Externalizable.writeExternal.


Write this out.







Inherited from org.apache.derby.impl.store.raw.data.PageBasicOperation:


findpagegetPagegetPageForRedoRecoverygetPageIdgetPageVersionneedsRedoreclaimPrepareLocksresetPageNumber







Field Detail




recordIdback to summary

protected int recordId






undoOpback to summary

private transient LogicalPageOperation undoOp
The operation to be rolled back








Constructor Detail




LogicalUndoOperationback to summary

pack-priv LogicalUndoOperation(BasePage page)






LogicalUndoOperationback to summary

pack-priv LogicalUndoOperation(BasePage page, int recordId, LogicalPageOperation op)
Set up a compensation operation during run time rollback






LogicalUndoOperationback to summary

public LogicalUndoOperation()
Return my format identifier.








Method Detail




doMeback to summary

public final void doMe(Transaction xact, LogInstant instant, LimitObjectInput in) throws StandardException, IOException
Implements org.apache.derby.iapi.store.raw.Loggable.doMe.

Apply the undo operation, in this implementation of the
RawStore, it can only call the undoMe method of undoOp



Parameters



xact:Transaction
the Transaction that is doing the rollback

instant:LogInstant
the log instant of this undo operation

in:LimitObjectInput
optional data



Exceptions



StandardException:
Standard Derby policy.

IOException:
Can be thrown by any of the methods of ObjectInput.










getPreparedLogback to summary

public final ByteArray getPreparedLog()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.getPreparedLog.

Implements org.apache.derby.iapi.store.raw.Loggable.getPreparedLog.

Doc from org.apache.derby.iapi.store.raw.Loggable.getPreparedLog.

The log operations are responsible to create the ByteArray, and the log
		operations should write out any optional data for the change to the 
        ByteArray.
		The ByteArray can be prepared when the log operation is constructed,
		or it can be prepared when getPreparedLog() is called.

		Called by the log manager to allow the log operation to pass the buffer
		which contains optional data that will be available in to doMe() 
        methods.






getTypeFormatIdback to summary

public int getTypeFormatId()
Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

Doc from org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

Get a universally unique identifier for the type of
this object.



Returns:int
The identifier. (A UUID stuffed in an array
of 16 bytes).








groupback to summary

public int group()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.group.

Implements org.apache.derby.iapi.store.raw.Loggable.group.

Doc from org.apache.derby.iapi.store.raw.Loggable.group.

Get the loggable's group value






readExternalback to summary

public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.readExternal.

Implements java.io.Externalizable.readExternal.

Read this in



Parameters



in:ObjectInput
Doc from java.io.Externalizable.readExternal.

the stream to read data from in order to restore the object



Exceptions



IOException:
error reading from log stream

ClassNotFoundException:
log stream corrupted










releaseResourceback to summary

public void releaseResource(Transaction xact)
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.releaseResource.

Implements org.apache.derby.iapi.store.raw.Loggable.releaseResource.

Doc from org.apache.derby.iapi.store.raw.Loggable.releaseResource.

Release any resource that was acquired for doMe for rollback or
recovery redo.

This resource is acquired in either generateUndo (if this is a
compensation operation during run time rollback or recovery rollback)
or in needsRedo (if this is during recovery redo).  The run time
transaction context should have all the resource already acquird for
run time roll forward, so there is no need to releaseResource during
run time roll forward.

This method must be safe to be called multiple times.






restoreMeback to summary

public void restoreMe(Transaction xact, BasePage undoPage, LogInstant CLRinstant, LimitObjectInput in)
Implements abstract org.apache.derby.impl.store.raw.data.PageBasicOperation.restoreMe.

Doc from org.apache.derby.impl.store.raw.data.PageBasicOperation.restoreMe.

Undo the change indicated by this log operation and optional data.
The page the undo should apply to is the latched undoPage.
The undoPage must be the same page as the doMe page and the undo
operation must restore the before image of the row that changed.  


 this can only be used under special circumstances: namely
table level locking, and no internal or nested transaction, and all
operations are rollec back with restoreMe instead of undoMe.


This method is here to support BeforeImageLogging



Parameters



xact:Transaction
the Transaction doing the rollback

undoPage:BasePage
the page to rollback changes on

CLRinstant:LogInstant
the log instant of this (PageUndo) operation

in:LimitObjectInput
optional data for the rollback operation










setUndoOpback to summary

public void setUndoOp(Undoable op)
Implements org.apache.derby.iapi.store.raw.Compensation.setUndoOp.

Set up a LogicalOperation during recovery redo.



Parameters



op:Undoable
Doc from org.apache.derby.iapi.store.raw.Compensation.setUndoOp.

the Undoable operation










toStringback to summary

public String toString()
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.toString.

DEBUG: Print self.



Returns:String
Doc from java.lang.Object.toString.

a string representation of the object








writeExternalback to summary

public void writeExternal(ObjectOutput out) throws IOException
Overrides org.apache.derby.impl.store.raw.data.PageBasicOperation.writeExternal.

Implements java.io.Externalizable.writeExternal.

Write this out.



Parameters



out:ObjectOutput
Doc from java.io.Externalizable.writeExternal.

the stream to write the object to



Exceptions



IOException:
error writing to log stream