org.apache.derby.impl.store.raw.log
Class LogRecord

java.lang.Object
  org.apache.derby.impl.store.raw.log.LogRecord

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, Formatable, TypedFormat

public class LogRecord
extends java.lang.Object
implements Formatable

The log record written out to disk. This log record includes:

The is a holder object that may be setup using the setValue() and re-used rather than creating a new object for each actual log record.

        The format of a log record is




See Also:
Serialized Form
Format ID
LOG_RECORD
                the formatId is written by FormatIdOutputStream when this object is
                written out by writeObject
Purpose
The log record described every change to the persistent store
Upgrade

Disk Layout
loggable group(CompressedInt)	the loggable's group value
                xactId(TransactionId)			The Transaction this log belongs to
                op(Loggable)					the log operation








Field Summary




private static int
formatLength



           



private  int
group



           



(package private)  java.io.ObjectInput
input



           



private  Loggable
op



           



private  TransactionId
xactId



           


 



Constructor Summary
LogRecord()



           
 



Method Summary




static int
formatOverhead()



           



 Loggable
getLoggable()



           



 RePreparable
getRePreparable()



           



static int
getStoredSize(int group,
              TransactionId xactId)



           



 TransactionId
getTransactionId()



           



 int
getTypeFormatId()



          Return my format identifier.



 Undoable
getUndoable()



           



 int
group()



           



 boolean
isAbort()



           



 boolean
isChecksum()



           



 boolean
isCLR()



           



 boolean
isCommit()



           



 boolean
isComplete()



           



 boolean
isFirst()



           



 boolean
isPrepare()



           



static int
maxGroupStoredSize()



           



static int
maxTransactionIdStoredSize(TransactionId tranId)



           



 void
readExternal(java.io.ObjectInput in)



          Read this in



 boolean
requiresPrepareLocks()



           



 void
setValue(TransactionId xactId,
         Loggable op)



           



 void
skipLoggable()



          Skip over the loggable.



 void
writeExternal(java.io.ObjectOutput out)



          Write this out.


 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 





Field Detail



xactId
private TransactionId xactId







op
private Loggable op







group
private int group







input
transient java.io.ObjectInput input







formatLength
private static final int formatLength








Constructor Detail



LogRecord
public LogRecord()






Method Detail



writeExternal
public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Write this out.


Specified by:
writeExternal in interface java.io.Externalizable



Throws:
java.io.IOException - error writing to log stream





readExternal
public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Read this in


Specified by:
readExternal in interface java.io.Externalizable



Throws:
java.io.IOException - error reading from log stream
java.lang.ClassNotFoundException - corrupted log stream





getTypeFormatId
public int getTypeFormatId()

Return my format identifier.


Specified by:
getTypeFormatId in interface TypedFormat



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





setValue
public void setValue(TransactionId xactId,
                     Loggable op)











formatOverhead
public static int formatOverhead()











maxGroupStoredSize
public static int maxGroupStoredSize()











maxTransactionIdStoredSize
public static int maxTransactionIdStoredSize(TransactionId tranId)











getStoredSize
public static int getStoredSize(int group,
                                TransactionId xactId)











getTransactionId
public TransactionId getTransactionId()
                               throws java.io.IOException,
                                      java.lang.ClassNotFoundException






Throws:
java.io.IOException
java.lang.ClassNotFoundException





getLoggable
public Loggable getLoggable()
                     throws java.io.IOException,
                            java.lang.ClassNotFoundException






Throws:
java.io.IOException
java.lang.ClassNotFoundException





getRePreparable
public RePreparable getRePreparable()
                             throws java.io.IOException,
                                    java.lang.ClassNotFoundException






Throws:
java.io.IOException
java.lang.ClassNotFoundException





skipLoggable
public void skipLoggable()
                  throws StandardException

Skip over the loggable.  Set the input stream to point ot after the
                loggable as if the entire log record has been sucked in by the log
                record






Throws:
StandardException - if the loggable is not found, log is corrupt





getUndoable
public Undoable getUndoable()
                     throws java.io.IOException,
                            java.lang.ClassNotFoundException






Throws:
java.io.IOException
java.lang.ClassNotFoundException





isCLR
public boolean isCLR()











isFirst
public boolean isFirst()











isComplete
public boolean isComplete()











isPrepare
public boolean isPrepare()











requiresPrepareLocks
public boolean requiresPrepareLocks()











isCommit
public boolean isCommit()











isAbort
public boolean isAbort()











group
public int group()











isChecksum
public boolean isChecksum()