org.apache.derby.impl.store.raw.data
Class RecordId

java.lang.Object
  extended by org.apache.derby.impl.store.raw.data.RecordId
All Implemented Interfaces:
Lockable, RecordHandle

public final class RecordId
extends java.lang.Object
implements RecordHandle

Implementation of RecordHandle.
MT - Mutable - Immutable identity : Thread Aware -
The methods of RecordHandle only access the identity of the object and so the object appears immutable to them, as required.
The methods of Lockable are single thread required.


Field Summary
private  PageKey pageId
          Page the record lives in.
private  int recordId
          The actual record id.
private  int slotNumberHint
          Last slot number this record id was at.
 
Fields inherited from interface org.apache.derby.iapi.store.raw.RecordHandle
DEALLOCATE_PROTECTION_HANDLE, FIRST_RECORD_ID, INVALID_RECORD_HANDLE, PREVIOUS_KEY_HANDLE, RESERVED1_RECORD_HANDLE, RESERVED4_RECORD_HANDLE, RESERVED5_RECORD_HANDLE
 
Constructor Summary
RecordId(ContainerKey container, long pageNumber, int recordId)
           
RecordId(PageKey pageId, int recordId)
           
RecordId(PageKey pageId, int recordId, int current_slot)
           
 
Method Summary
 boolean equals(java.lang.Object ref)
          Implement value equality.
 ContainerKey getContainerId()
          Return the identity of my container.
 int getId()
          Get my record id.
 java.lang.Object getPageId()
          Return the identity of my Page.
 long getPageNumber()
          Get my page number.
 int getSlotNumberHint()
          What slot number might the record be at?
 int hashCode()
          Return a hashcode based on value.
 boolean lockAttributes(int flag, java.util.Hashtable attributes)
          This lockable wants to participate in the Virtual Lock table.
 boolean lockerAlwaysCompatible()
          Is a caller that holds a lock compatible with themselves?
 void lockEvent(Latch lockInfo)
          Lock me.
 boolean requestCompatible(java.lang.Object requestedQualifier, java.lang.Object grantedQualifier)
          Determine if this request can be granted.
 java.lang.String toString()
           
 void unlockEvent(Latch lockInfo)
          Unlock me.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

pageId

private final PageKey pageId
Page the record lives in. MT - Immutable


recordId

private final int recordId
The actual record id. MT - Immutable


slotNumberHint

private transient int slotNumberHint
Last slot number this record id was at.

Constructor Detail

RecordId

public RecordId(ContainerKey container,
                long pageNumber,
                int recordId)

RecordId

public RecordId(PageKey pageId,
                int recordId)

RecordId

public RecordId(PageKey pageId,
                int recordId,
                int current_slot)
Method Detail

getId

public int getId()
Get my record id.
MT - thread safe

Specified by:
getId in interface RecordHandle
See Also:
RecordHandle.getId()

getPageNumber

public long getPageNumber()
Get my page number.
MT - thread safe

Specified by:
getPageNumber in interface RecordHandle
See Also:
RecordHandle.getPageNumber()

getPageId

public java.lang.Object getPageId()
Description copied from interface: RecordHandle
Return the identity of my Page.

Specified by:
getPageId in interface RecordHandle

getContainerId

public ContainerKey getContainerId()
Description copied from interface: RecordHandle
Return the identity of my container.

Specified by:
getContainerId in interface RecordHandle

getSlotNumberHint

public int getSlotNumberHint()
What slot number might the record be at?

The raw store guarantees that the record handle of a record will not change, but its slot number may. When a RecordId is constructed the caller could have provided a slot number, if so return that slot number hint here. If a hint was not provided then the default Page.FIRST_SLOT_NUMBER will be returned.

Specified by:
getSlotNumberHint in interface RecordHandle
Returns:
The slot number the record handle may be at.

lockEvent

public void lockEvent(Latch lockInfo)
Lock me.
MT - Single thread required (methods of Lockable)

Specified by:
lockEvent in interface Lockable
See Also:
Lockable.lockEvent(org.apache.derby.iapi.services.locks.Latch)

requestCompatible

public boolean requestCompatible(java.lang.Object requestedQualifier,
                                 java.lang.Object grantedQualifier)
Determine if this request can be granted.

Implements the grant/wait lock logic for row locks. See the table in RowLock for more information.
MT - Single thread required (methods of Lockable)

Specified by:
requestCompatible in interface Lockable
See Also:
Lockable.requestCompatible(java.lang.Object, java.lang.Object)

lockerAlwaysCompatible

public boolean lockerAlwaysCompatible()
Is a caller that holds a lock compatible with themselves?

Row locks held in the same transaction are always compatible with themselves.
MT - Single thread required (methods of Lockable)

Specified by:
lockerAlwaysCompatible in interface Lockable
See Also:
Lockable.lockerAlwaysCompatible()

unlockEvent

public void unlockEvent(Latch lockInfo)
Unlock me.
MT - Single thread required (methods of Lockable)

Specified by:
unlockEvent in interface Lockable
See Also:
Lockable.unlockEvent(org.apache.derby.iapi.services.locks.Latch)

equals

public boolean equals(java.lang.Object ref)
Implement value equality.
MT - Thread safe

Overrides:
equals in class java.lang.Object

hashCode

public int hashCode()
Return a hashcode based on value.
MT - thread safe

Overrides:
hashCode in class java.lang.Object

toString

public java.lang.String toString()
Overrides:
toString in class java.lang.Object

lockAttributes

public boolean lockAttributes(int flag,
                              java.util.Hashtable attributes)
This lockable wants to participate in the Virtual Lock table.

Specified by:
lockAttributes in interface Lockable
Parameters:
flag - use the bits in this int to decide if the user is interested in this kind of lockable object. The bits are defined in VirtualLockTable. For instance, the user may only ask for TABLE_AND_ROWLOCK and if this is not a table or row lock, then don't paritipate.
attributes - if this decides to participate, put all relavent attributes into the Hashtable. The complete list of interesting attributes is listed in VirtualLockTable. The following attributes must be present for all participating lockables: VirtualLockTable.LOCKNAME, VirtualLockTable.LOCKTYPE, either VirtualLockTable.CONTAINERID or VirtualLockTable.CONGLOMID,

MT - this routine must be MP safe, caller will not be single threading the lock manager.

Returns:
true if this object has diagnostic information to add to the virtual lock table. If this object either does not want to participate in the diagnostic virtual lock table or none of the attributes requested are attributes of this lock, returns false.
See Also:
VirtualLockTable

Built on Thu 2012-03-29 21:53:33+0000, from revision ???

Apache Derby V10.6 Internals - Copyright © 2004,2007 The Apache Software Foundation. All Rights Reserved.