Class PurgeOperation

java.lang.Object

org.apache.derby.impl.store.raw.data.PageBasicOperation

org.apache.derby.impl.store.raw.data.PhysicalPageOperation

org.apache.derby.impl.store.raw.data.PurgeOperation

All Implemented Interfaces:

Externalizable, Serializable, Formatable, TypedFormat, Loggable, RePreparable, Undoable

public final class PurgeOperation
extends PhysicalPageOperation

USE WITH EXTREME Caution: Purge records from a Page. Represents purging of a range of rows from the page.

See Also:

• Page.purgeAtSlot(int, int, boolean)
• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected int	num_rows
protected ByteArray	preparedLog
protected int[]	recordIds
protected int	slot

Fields inherited from class PageBasicOperation

containerHdl, foundHere, page

Fields inherited from interface Loggable

ABORT, BI_LOG, CHECKSUM, COMMIT, COMPENSATION, FILE_RESOURCE, FIRST, LAST, PREPARE, RAWSTORE, XA_NEEDLOCK

Constructor Summary

Constructors

Constructor	Description
PurgeOperation()
PurgeOperation(RawTransaction t, BasePage page, int slot, int num_rows, int[] recordIds, boolean needDataLogged)

Method Summary

Modifier and Type	Method	Description
void	doMe(Transaction xact, LogInstant instant, LimitObjectInput in)	Apply the purge operation to the page.
ByteArray	getPreparedLog()	the default for optional data is set to null.
int	getTypeFormatId()	Return my format identifier.
void	readExternal(ObjectInput in)	Read this in
void	restoreMe(Transaction xact, BasePage undoPage, LogInstant CLRInstant, LimitObjectInput in)	restore the before image of the page
String	toString()	DEBUG: Print self.
void	undoMe(Transaction xact, BasePage undoPage, LogInstant CLRInstant, LimitObjectInput in)	Undo the purge operation on the page.
void	writeExternal(ObjectOutput out)
private void	writeOptionalDataToBuffer(RawTransaction t, boolean needDataLogged)	Write out the purged record from the page.

Methods inherited from class PhysicalPageOperation

generateUndo

Methods inherited from class PageBasicOperation

findpage, getPage, getPageForRedoRecovery, getPageId, getPageVersion, group, needsRedo, reclaimPrepareLocks, releaseResource, resetPageNumber

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface Loggable

group, needsRedo, releaseResource

Field Details

slot

protected int slot

num_rows

protected int num_rows

recordIds

protected int[] recordIds

preparedLog

protected transient ByteArray preparedLog

Constructor Details

PurgeOperation

PurgeOperation(RawTransaction t,
 BasePage page,
 int slot,
 int num_rows,
 int[] recordIds,
 boolean needDataLogged)
        throws StandardException

Throws:

StandardException

PurgeOperation

public PurgeOperation()

Method Details

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Overrides:

writeExternal in class PageBasicOperation

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
ClassNotFoundException

Read this in

Specified by:

readExternal in interface Externalizable

Overrides:

readExternal in class PageBasicOperation

Throws:

IOException - error reading from log stream

ClassNotFoundException - log stream corrupted

getTypeFormatId

public int getTypeFormatId()

Return my format identifier.

Returns:

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

doMe

public void doMe(Transaction xact,
 LogInstant instant,
 LimitObjectInput in)
          throws StandardException,
IOException

Apply the purge operation to the page.

Parameters:

xact - the Transaction

instant - the log instant of this operation

in - optional data

Throws:

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

StandardException - Standard Derby policy.

See Also:

• Loggable.doMe(Transaction, LogInstant, LimitObjectInput)

undoMe

public void undoMe(Transaction xact,
 BasePage undoPage,
 LogInstant CLRInstant,
 LimitObjectInput in)
            throws StandardException,
IOException

Undo the purge operation on the page.

Specified by:

undoMe in class PhysicalPageOperation

Parameters:

xact - the Transaction doing the rollback

undoPage - the page to rollback changes on

CLRInstant - the log instant of this (PageUndo) operation

in - optional data for the rollback operation

Throws:

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

StandardException - Standard Derby policy.

See Also:

• PhysicalPageOperation.undoMe(Transaction, BasePage, LogInstant, LimitObjectInput)

restoreMe

public void restoreMe(Transaction xact,
 BasePage undoPage,
 LogInstant CLRInstant,
 LimitObjectInput in)
               throws StandardException,
IOException

restore the before image of the page

Specified by:

restoreMe in class PageBasicOperation

Parameters:

xact - the Transaction doing the rollback

undoPage - the page to rollback changes on

CLRInstant - the log instant of this (PageUndo) operation

in - optional data for the rollback operation

Throws:

StandardException - Standard Derby Error Policy

IOException - problem reading the complete log record from the input stream

getPreparedLog

public ByteArray getPreparedLog()

Description copied from class: PageBasicOperation

the default for optional data is set to null. If an operation has optional data, the operation need to prepare the optional data for this method. WARNING: If a log operation extends this class, and the operation has optional data, it MUST overwrite this method to return a ByteArray that contains the optional data.

Specified by:

getPreparedLog in interface Loggable

Overrides:

getPreparedLog in class PageBasicOperation

writeOptionalDataToBuffer

private void writeOptionalDataToBuffer(RawTransaction t,
 boolean needDataLogged)
                                throws StandardException,
IOException

Write out the purged record from the page. Used for undo only.

Throws:

IOException - Can be thrown by any of the methods of ObjectOutput.

StandardException - Standard Derby policy.

toString

public String toString()

DEBUG: Print self.

Overrides:

toString in class PageBasicOperation