org.apache.derby.impl.store.access.btree.index
Class B2IRowLocking2

java.lang.Object
  extended byorg.apache.derby.impl.store.access.btree.index.B2IRowLocking3
      extended byorg.apache.derby.impl.store.access.btree.index.B2IRowLockingRR
          extended byorg.apache.derby.impl.store.access.btree.index.B2IRowLocking2
All Implemented Interfaces:
BTreeLockingPolicy
Direct Known Subclasses:
B2IRowLocking1

class B2IRowLocking2
extends B2IRowLockingRR
implements BTreeLockingPolicy


Field Summary
protected  ConglomerateController base_cc
          The container id of the base container for this index.
protected  OpenBTree open_btree
          The OpenBtree to use if we have to lock anything in the btree vs.
 
Constructor Summary
(package private) B2IRowLocking2(Transaction rawtran, int lock_level, LockingPolicy locking_policy, ConglomerateController base_cc, OpenBTree open_btree)
          Constructors for This class:
 
Method Summary
protected  boolean _lockScanRow(OpenBTree open_btree, BTree btree, BTreeRowPosition pos, boolean request_row_lock, boolean request_scan_lock, FetchDescriptor lock_fetch_desc, DataValueDescriptor[] lock_template, RowLocation lock_row_loc, boolean previous_key_lock, boolean forUpdate, int lock_operation)
          Lock a row as part of doing the scan.
 boolean lockNonScanPreviousRow(BTree btree, LeafControlRow current_leaf, int current_slot, FetchDescriptor lock_fetch_desc, DataValueDescriptor[] lock_template, RowLocation lock_row_loc, OpenBTree open_btree, int lock_operation, int lock_duration)
          Lock the row previous to the input row.
 boolean lockNonScanRow(BTree btree, LeafControlRow current_leaf, LeafControlRow aux_leaf, DataValueDescriptor[] current_row, int lock_operation)
          Lock the in memory row.
 boolean lockNonScanRowOnPage(BTree btree, LeafControlRow current_leaf, int current_slot, FetchDescriptor lock_fetch_desc, DataValueDescriptor[] lock_template, RowLocation lock_row_loc, int lock_operation)
          Lock the row at the given slot.
 boolean lockScan(LeafControlRow current_leaf, ControlRow aux_control_row, boolean forUpdate, int lock_operation)
          Lock a control row page for scan.
 boolean lockScanCommittedDeletedRow(OpenBTree open_btree, LeafControlRow leaf, DataValueDescriptor[] template, FetchDescriptor lock_fetch_desc, int slot_no)
          Lock a btree row to determine if it is a committed deleted row.
 boolean lockScanForReclaimSpace(LeafControlRow current_leaf)
          Lock a control row page for reclaiming deleted rows.
 boolean lockScanRow(OpenBTree open_btree, BTree btree, BTreeRowPosition pos, boolean request_scan_lock, FetchDescriptor lock_fetch_desc, DataValueDescriptor[] lock_template, RowLocation lock_row_loc, boolean previous_key_lock, boolean forUpdate, int lock_operation)
          Lock a row as part of doing the scan.
 void unlockScan(long page_number)
          Release the lock gotten by calling lockScan.
 void unlockScanRecordAfterRead(BTreeRowPosition pos, boolean forUpdate)
          Release read lock on a row.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.derby.impl.store.access.btree.BTreeLockingPolicy
lockNonScanPreviousRow, lockNonScanRow, lockNonScanRowOnPage, lockScan, lockScanCommittedDeletedRow, lockScanForReclaimSpace, lockScanRow, unlockScan
 

Field Detail

base_cc

protected ConglomerateController base_cc
The container id of the base container for this index. Used to build record handles to make lock calls on.


open_btree

protected OpenBTree open_btree
The OpenBtree to use if we have to lock anything in the btree vs. base row locking.

Constructor Detail

B2IRowLocking2

B2IRowLocking2(Transaction rawtran,
               int lock_level,
               LockingPolicy locking_policy,
               ConglomerateController base_cc,
               OpenBTree open_btree)
Constructors for This class:

Method Detail

unlockScanRecordAfterRead

public void unlockScanRecordAfterRead(BTreeRowPosition pos,
                                      boolean forUpdate)
                               throws StandardException
Release read lock on a row.

Specified by:
unlockScanRecordAfterRead in interface BTreeLockingPolicy
Overrides:
unlockScanRecordAfterRead in class B2IRowLockingRR
Parameters:
forUpdate - Is the scan for update or for read only.
Throws:
StandardException

lockScanRow

public boolean lockScanRow(OpenBTree open_btree,
                           BTree btree,
                           BTreeRowPosition pos,
                           boolean request_scan_lock,
                           FetchDescriptor lock_fetch_desc,
                           DataValueDescriptor[] lock_template,
                           RowLocation lock_row_loc,
                           boolean previous_key_lock,
                           boolean forUpdate,
                           int lock_operation)
                    throws StandardException
Lock a row as part of doing the scan.

Lock the row at the given slot (or the previous row if slot is 0). Get the scan lock on the page if "request_scan_lock" is true.

If this routine returns true all locks were acquired while maintaining the latch on leaf. If this routine returns false, locks may or may not have been acquired, and the routine should be called again after the client has researched the tree to reget the latch on the appropriate page. (p> As a side effect stores the value of the record handle of the current scan lock.

Specified by:
lockScanRow in interface BTreeLockingPolicy
Overrides:
lockScanRow in class B2IRowLocking3
Parameters:
open_btree - The open_btree to associate latches with - used if routine has to scan backward.
btree - the conglomerate info.
request_scan_lock - Whether to request the page scan lock, should only be requested once per page in the scan.
previous_key_lock - Is this a previous key lock call?
forUpdate - Is the scan for update or for read only.
Returns:
Whether locks were acquired without releasing latch on leaf.
Throws:
StandardException - Standard exception policy.

_lockScanRow

protected boolean _lockScanRow(OpenBTree open_btree,
                               BTree btree,
                               BTreeRowPosition pos,
                               boolean request_row_lock,
                               boolean request_scan_lock,
                               FetchDescriptor lock_fetch_desc,
                               DataValueDescriptor[] lock_template,
                               RowLocation lock_row_loc,
                               boolean previous_key_lock,
                               boolean forUpdate,
                               int lock_operation)
                        throws StandardException
Lock a row as part of doing the scan.

Lock the row at the given slot (or the previous row if slot is 0). Get the scan lock on the page if "request_scan_lock" is true.

If this routine returns true all locks were acquired while maintaining the latch on leaf. If this routine returns false, locks may or may not have been acquired, and the routine should be called again after the client has researched the tree to reget the latch on the appropriate page. (p> As a sided effect stores the value of the record handle of the current scan lock.

Parameters:
open_btree - The open_btree to associate latches with - used if routine has to scan backward.
btree - the conglomerate info.
request_row_lock - Whether to request the row lock, should only be requested once per page in the scan.
request_scan_lock - Whether to request the page scan lock, should only be requested once per page in the scan.
previous_key_lock - Is this a previous key lock call?
forUpdate - Is the scan for update or for read only.
Returns:
Whether locks were acquired without releasing latch on leaf.
Throws:
StandardException - Standard exception policy.

lockScan

public boolean lockScan(LeafControlRow current_leaf,
                        ControlRow aux_control_row,
                        boolean forUpdate,
                        int lock_operation)
                 throws StandardException
Lock a control row page for scan.

Scanners get shared lock on the page while positioned on a row within the page, splitter/purgers/mergers get exclusive lock on the page. See BTree.lockScan() for more info.

Specified by:
lockScan in interface BTreeLockingPolicy
Parameters:
current_leaf - The lock is associated with this page in the btree. This control row is unlatched if the routine has to wait on the lock.
aux_control_row - If non-null, this control row is unlatched if the routine has to wait on the lock.
forUpdate - Whether to wait for lock.
Throws:
StandardException - Standard exception policy.

lockScanForReclaimSpace

public boolean lockScanForReclaimSpace(LeafControlRow current_leaf)
                                throws StandardException
Lock a control row page for reclaiming deleted rows.

When reclaiming deleted rows during split need to get an exclusive scan lock on the page, which will mean there are no other scans positioned on the page. If there are other scans positioned, just give up on reclaiming space now.

Specified by:
lockScanForReclaimSpace in interface BTreeLockingPolicy
Returns:
true if lock was granted nowait, else false and not lock was granted.
Throws:
StandardException - Standard exception policy.

lockScanCommittedDeletedRow

public boolean lockScanCommittedDeletedRow(OpenBTree open_btree,
                                           LeafControlRow leaf,
                                           DataValueDescriptor[] template,
                                           FetchDescriptor lock_fetch_desc,
                                           int slot_no)
                                    throws StandardException
Lock a btree row to determine if it is a committed deleted row.

Specified by:
lockScanCommittedDeletedRow in interface BTreeLockingPolicy
Parameters:
open_btree - The conglomerate we are locking.
leaf - The leaf page with the row to lock.
template - Empty full template row, to read row into.
slot_no - The slot of row on "current_leaf"
Throws:
StandardException - Standard exception policy.
See Also:
BTreeLockingPolicy.lockScanCommittedDeletedRow(org.apache.derby.impl.store.access.btree.OpenBTree, org.apache.derby.impl.store.access.btree.LeafControlRow, org.apache.derby.iapi.types.DataValueDescriptor[], org.apache.derby.iapi.store.raw.FetchDescriptor, int)

unlockScan

public void unlockScan(long page_number)
Release the lock gotten by calling lockScan. This call can only be made to release read scan locks, write scan locks must be held until end of transaction.

See BTree.unlockScan() for more info.

Specified by:
unlockScan in interface BTreeLockingPolicy
Parameters:
page_number - page number of page that lockScan was called on.

lockNonScanPreviousRow

public boolean lockNonScanPreviousRow(BTree btree,
                                      LeafControlRow current_leaf,
                                      int current_slot,
                                      FetchDescriptor lock_fetch_desc,
                                      DataValueDescriptor[] lock_template,
                                      RowLocation lock_row_loc,
                                      OpenBTree open_btree,
                                      int lock_operation,
                                      int lock_duration)
                               throws StandardException
Lock the row previous to the input row.

See BTree.lockPreviousRow() for more info.

Specified by:
lockNonScanPreviousRow in interface BTreeLockingPolicy
Parameters:
btree - The conglomerate we are locking.
current_leaf - Latched current leaf where "current" key is.
current_slot - The slot of row on "current_leaf"
open_btree - The open_btree to associate latches with - used if routine has to scan backward.
lock_duration - For what duration should the lock be held, if INSTANT_DURATION, then the routine will guarantee that lock was acquired while holding the latch, but then immediately release the lock. If COMMIT_DURATION or MANUAL_DURATION then the lock be held when routine returns successfully.
Throws:
StandardException - Standard exception policy.

lockNonScanRow

public boolean lockNonScanRow(BTree btree,
                              LeafControlRow current_leaf,
                              LeafControlRow aux_leaf,
                              DataValueDescriptor[] current_row,
                              int lock_operation)
                       throws StandardException
Lock the in memory row.

See BTree.lockRow() for more info.

Specified by:
lockNonScanRow in interface BTreeLockingPolicy
Parameters:
btree - The conglomerate we are locking.
current_leaf - If non-null, this leaf is unlatched if the routine has to wait on the lock.
aux_leaf - If non-null, this leaf is unlatched if the routine has to wait on the lock.
current_row - In memory, objectified "current" row.
Throws:
StandardException - Standard exception policy.

lockNonScanRowOnPage

public boolean lockNonScanRowOnPage(BTree btree,
                                    LeafControlRow current_leaf,
                                    int current_slot,
                                    FetchDescriptor lock_fetch_desc,
                                    DataValueDescriptor[] lock_template,
                                    RowLocation lock_row_loc,
                                    int lock_operation)
                             throws StandardException
Description copied from interface: BTreeLockingPolicy
Lock the row at the given slot.

If this routine returns true all locks were acquired while maintaining the latch on leaf. If this routine returns false, locks may or may not have been acquired, and the routine should be called again after the client has researched the tree to reget the latch on the appropriate page.

Specified by:
lockNonScanRowOnPage in interface BTreeLockingPolicy
Parameters:
btree - the conglomerate info.
current_leaf - The control row of the current leaf to lock.
current_slot - The slot position of the row to lock.
Returns:
Whether locks were acquired without releasing latch on leaf.
Throws:
StandardException - Standard exception policy.


Apache Derby V10.0 Engine Documentation - Copyright © 1997,2004 The Apache Software Foundation or its licensors, as applicable.