/* Copyright (c) 2001-2009, The HSQL Development Group
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the HSQL Development Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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package org.hsqldb_voltpatches;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import org.hsqldb_voltpatches.HsqlNameManager.HsqlName;
import org.hsqldb_voltpatches.lib.DoubleIntIndex;
import org.hsqldb_voltpatches.lib.HashMap;
import org.hsqldb_voltpatches.lib.HsqlArrayList;
import org.hsqldb_voltpatches.lib.HsqlDeque;
import org.hsqldb_voltpatches.lib.IntKeyHashMapConcurrent;
import org.hsqldb_voltpatches.lib.Iterator;
import org.hsqldb_voltpatches.lib.LongDeque;
import org.hsqldb_voltpatches.lib.MultiValueHashMap;
import org.hsqldb_voltpatches.persist.CachedObject;
import org.hsqldb_voltpatches.persist.PersistentStore;
import org.hsqldb_voltpatches.store.ValuePool;
/**
* Manages rows involved in transactions
*
* @author Fred Toussi (fredt@users dot sourceforge.net)
* @version 2.0.0
* @since 2.0.0
*/
public class TransactionManager {
Database database;
boolean mvcc = false;
//
ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
ReentrantReadWriteLock.WriteLock writeLock = lock.writeLock();
// functional unit - sessions involved in live transactions
/** live transactions keeping committed transactions from being merged */
LongDeque liveTransactionTimestamps = new LongDeque();
AtomicLong globalChangeTimestamp = new AtomicLong();
// functional unit - merged committed transactions
HsqlDeque committedTransactions = new HsqlDeque();
LongDeque committedTransactionTimestamps = new LongDeque();
// functional unit - cached table transactions
/** Map : rowID -> RowAction */
public IntKeyHashMapConcurrent rowActionMap =
new IntKeyHashMapConcurrent(10000);
//
//
HashMap tableWriteLocks = new HashMap();
MultiValueHashMap tableReadLocks = new MultiValueHashMap();
TransactionManager(Database db) {
database = db;
}
public void setMVCC(boolean value) {
writeLock.lock();
try {
synchronized (liveTransactionTimestamps) {
if (liveTransactionTimestamps.isEmpty()) {
mvcc = value;
return;
}
}
} finally {
writeLock.unlock();
}
throw Error.error(ErrorCode.X_25001);
}
public void completeActions(Session session) {
Object[] list = session.rowActionList.getArray();
int limit = session.rowActionList.size();
boolean canComplete = true;
writeLock.lock();
try {
for (int i = session.actionIndex; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (rowact.complete(session, session.tempSet)) {
continue;
}
canComplete = false;
if (session.isolationMode == SessionInterface
.TX_REPEATABLE_READ || session
.isolationMode == SessionInterface.TX_SERIALIZABLE) {
session.abortTransaction = true;
break;
}
}
for (int i = session.actionIndex; canComplete && i < limit; i++) {
RowAction action = (RowAction) list[i];
if (!action.table.isLogged) {
continue;
}
Row row = action.memoryRow;
if (row == null) {
PersistentStore store =
session.sessionData.getRowStore(action.table);
row = (Row) store.get(action.getPos(), false);
}
Object[] data = row.getData();
try {
int actionType =
action.getActionType(session.actionTimestamp);
if (actionType == RowActionBase.ACTION_INSERT) {
database.logger.writeInsertStatement(session,
action.table,
data);
} else if (actionType == RowActionBase.ACTION_DELETE) {
database.logger.writeDeleteStatement(session,
action.table,
data);
} else if (actionType == RowActionBase.ACTION_NONE) {
// no logging
} else {
throw Error.runtimeError(ErrorCode.U_S0500,
"TransactionManager");
}
} catch (HsqlException e) {
// can put db in special state
}
}
if (!canComplete && !session.abortTransaction) {
session.redoAction = true;
rollbackAction(session);
if (!session.tempSet.isEmpty()) {
session.latch.setCount(session.tempSet.size());
for (int i = 0; i < session.tempSet.size(); i++) {
Session current = (Session) session.tempSet.get(i);
current.waitingSessions.add(session);
// waitedSessions.put(current, session);
// waitingSessions.put(session, current);
}
}
}
} finally {
writeLock.unlock();
session.tempSet.clear();
}
}
public boolean prepareCommitActions(Session session) {
Object[] list = session.rowActionList.getArray();
int limit = session.rowActionList.size();
if (session.abortTransaction) {
// System.out.println("cascade fail " + session + " " + session.actionTimestamp);
return false;
}
try {
writeLock.lock();
for (int i = 0; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (!rowact.canCommit(session, session.tempSet)) {
// System.out.println("commit conflicts " + session + " " + session.actionTimestamp);
return false;
}
}
session.actionTimestamp = nextChangeTimestamp();
for (int i = 0; i < limit; i++) {
RowAction action = (RowAction) list[i];
action.prepareCommit(session);
}
for (int i = 0; i < session.tempSet.size(); i++) {
Session current = (Session) session.tempSet.get(i);
current.abortTransaction = true;
}
return true;
} finally {
writeLock.unlock();
session.tempSet.clear();
}
}
public boolean commitTransaction(Session session) {
if (session.abortTransaction) {
// System.out.println("cascade fail " + session + " " + session.actionTimestamp);
return false;
}
int limit = session.rowActionList.size();
Object[] list = limit == 0 ? ValuePool.emptyObjectArray
: session.rowActionList.getArray();
try {
writeLock.lock();
for (int i = 0; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (!rowact.canCommit(session, session.tempSet)) {
// System.out.println("commit conflicts " + session + " " + session.actionTimestamp);
return false;
}
}
endTransaction(session);
if (limit == 0) {
if (!mvcc) {
endTransactionTPL(session);
}
try {
session.logSequences();
if (mvcc) {
database.logger.writeCommitStatement(session);
}
} catch (HsqlException e) {}
return true;
}
// new actionTimestamp used for commitTimestamp
session.actionTimestamp = nextChangeTimestamp();
for (int i = 0; i < limit; i++) {
RowAction action = (RowAction) list[i];
action.commit(session);
}
for (int i = 0; i < session.tempSet.size(); i++) {
Session current = (Session) session.tempSet.get(i);
current.abortTransaction = true;
}
for (int i = 0; i < limit; i++) {
RowAction action = (RowAction) list[i];
if (action.table.hasLobColumn) {
int type = action.getCommitType(session.actionTimestamp);
switch (type) {
case RowActionBase.ACTION_INSERT :
Row row = action.memoryRow;
if (row == null) {
PersistentStore store =
session.sessionData.getRowStore(
action.table);
row = (Row) store.get(action.getPos(), false);
}
action.table.addLobUsageCount(session,
row.getData());
break;
default :
}
}
if (action.table.tableType == TableBase.TEXT_TABLE) {
PersistentStore store =
session.sessionData.getRowStore(action.table);
int type = action.getCommitType(session.actionTimestamp);
switch (type) {
case RowActionBase.ACTION_DELETE :
store.removePersistence(action.getPos());
break;
case RowActionBase.ACTION_INSERT :
Row row = (Row) store.get(action.getPos(), false);
store.commitPersistence(row);
break;
default :
}
}
}
// session.actionTimestamp is the committed tx timestamp
if (getFirstLiveTransactionTimestamp() > session.actionTimestamp) {
mergeTransaction(session, list, 0, limit,
session.actionTimestamp);
rowActionMapRemoveTransaction(list, 0, limit, true);
} else {
list = session.rowActionList.toArray();
addToCommittedQueue(session, list);
}
try {
session.logSequences();
database.logger.writeCommitStatement(session);
} catch (HsqlException e) {}
//
if (mvcc) {
if (!session.waitingSessions.isEmpty()) {
for (int i = 0; i < session.waitingSessions.size(); i++) {
Session current =
(Session) session.waitingSessions.get(i);
current.latch.countDown();
}
session.waitingSessions.clear();
}
} else {
endTransactionTPL(session);
}
return true;
} finally {
writeLock.unlock();
session.tempSet.clear();
}
}
public void rollback(Session session) {
session.abortTransaction = false;
session.actionTimestamp = nextChangeTimestamp();
rollbackPartial(session, 0, session.transactionTimestamp);
endTransaction(session);
if (!mvcc) {
try {
writeLock.lock();
endTransactionTPL(session);
} finally {
writeLock.unlock();
}
}
}
public void rollbackSavepoint(Session session, int index) {
long timestamp = session.sessionContext.savepointTimestamps.get(index);
Integer oi = (Integer) session.sessionContext.savepoints.get(index);
int start = oi.intValue();
while (session.sessionContext.savepoints.size() > index + 1) {
session.sessionContext.savepoints.remove(
session.sessionContext.savepoints.size() - 1);
session.sessionContext.savepointTimestamps.removeLast();
}
rollbackPartial(session, start, timestamp);
}
public void rollbackAction(Session session) {
rollbackPartial(session, session.actionIndex, session.actionTimestamp);
}
/**
* rollback the row actions from start index in list and
* the given timestamp
*/
void rollbackPartial(Session session, int start, long timestamp) {
Object[] list = session.rowActionList.getArray();
int limit = session.rowActionList.size();
if (start == limit) {
return;
}
for (int i = start; i < limit; i++) {
RowAction action = (RowAction) list[i];
if (action != null) {
action.rollback(session, timestamp);
} else {
System.out.println("null action in rollback " + start);
}
}
// rolled back transactions can always be merged as they have never been
// seen by other sessions
mergeRolledBackTransaction(session.rowActionList.getArray(), start,
limit);
rowActionMapRemoveTransaction(session.rowActionList.getArray(), start,
limit, false);
session.rowActionList.setSize(start);
}
public RowAction addDeleteAction(Session session, Table table, Row row) {
RowAction action;
synchronized (row) {
action = RowAction.addAction(session, RowActionBase.ACTION_DELETE,
table, row);
}
session.rowActionList.add(action);
if (!row.isMemory()) {
rowActionMap.put(action.getPos(), action);
}
return action;
}
public void addInsertAction(Session session, Table table, Row row) {
RowAction action = row.rowAction;
if (action == null) {
System.out.println("null insert action " + session + " "
+ session.actionTimestamp);
}
session.rowActionList.add(action);
if (!row.isMemory()) {
rowActionMap.put(action.getPos(), action);
}
}
// functional unit - row comparison
/**
* Used for inserting rows into unique indexes
*/
/** @todo test skips some equal rows because it relies on getPos() */
int compareRowForInsert(Row newRow, Row existingRow) {
// only allow new inserts over rows deleted by the same session
if (newRow.rowAction != null
&& !canRead(newRow.rowAction.session, existingRow)) {
return newRow.getPos() - existingRow.getPos();
}
return 0;
}
// functional unit - accessibility of rows
public boolean canRead(Session session, Row row) {
synchronized (row) {
RowAction action = row.rowAction;
if (action == null) {
return true;
}
return action.canRead(session);
}
}
public boolean isDeleted(Session session, Row row) {
synchronized (row) {
RowAction action = row.rowAction;
if (action == null) {
return false;
}
return !action.canRead(session);
}
}
public boolean canRead(Session session, int id) {
RowAction action = (RowAction) rowActionMap.get(id);
return action == null ? true
: action.canRead(session);
}
void rowActionMapRemoveTransaction(Object[] list, int start, int limit,
boolean commit) {
for (int i = start; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (!rowact.isMemory) {
synchronized (rowact) {
if (rowact.type == RowActionBase.ACTION_NONE
|| rowact.type
== RowActionBase.ACTION_DELETE_FINAL) {
int pos = rowact.getPos();
rowActionMap.remove(pos);
}
}
}
}
deleteRows(list, start, limit, commit);
}
void deleteRows(Object[] list, int start, int limit, boolean commit) {
for (int i = start; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (rowact.type == RowActionBase.ACTION_DELETE_FINAL) {
try {
rowact.type = RowActionBase.ACTION_DELETE_COMMITTED;
PersistentStore store =
rowact.session.sessionData.getRowStore(rowact.table);
Row row = rowact.memoryRow;
if (row == null) {
row = (Row) store.get(rowact.getPos(), false);
}
if (commit && rowact.table.hasLobColumn) {
Object[] data = row.getData();
rowact.table.removeLobUsageCount(rowact.session, data);
}
store.delete(row);
} catch (HsqlException e) {
// throw unexpectedException(e.getMessage());
}
}
}
}
/**
* add transaction info to a row just loaded from the cache. called only
* for CACHED tables
*/
public void setTransactionInfo(CachedObject object) {
Row row = (Row) object;
if (row.rowAction != null) {
return;
}
RowAction rowact = (RowAction) rowActionMap.get(row.position);
row.rowAction = rowact;
}
/**
* merge a given list of transaction rollback action with given timestamp
*/
void mergeRolledBackTransaction(Object[] list, int start, int limit) {
for (int i = start; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (rowact == null || rowact.type == RowActionBase.ACTION_NONE
|| rowact.type == RowActionBase.ACTION_DELETE_FINAL) {
continue;
}
Row row = rowact.memoryRow;
if (row == null) {
PersistentStore store =
rowact.session.sessionData.getRowStore(rowact.table);
row = (Row) store.get(rowact.getPos(), false);
}
if (row == null) {
continue;
}
synchronized (row) {
rowact.mergeRollback(row);
}
}
// } catch (Throwable t) {
// System.out.println("throw in merge");
// t.printStackTrace();
// }
}
/**
* add a list of actions to the end of queue
*/
void addToCommittedQueue(Session session, Object[] list) {
synchronized (committedTransactionTimestamps) {
// add the txList according to commit timestamp
committedTransactions.addLast(list);
// get session commit timestamp
committedTransactionTimestamps.addLast(session.actionTimestamp);
/* debug 190
if (committedTransactions.size() > 64) {
System.out.println("******* excessive transaction queue");
}
// debug 190 */
}
}
/**
* expire all committed transactions that are no longer in scope
*/
void mergeExpiredTransactions(Session session) {
long timestamp = getFirstLiveTransactionTimestamp();
while (true) {
long commitTimestamp = 0;
Object[] actions = null;
synchronized (committedTransactionTimestamps) {
if (committedTransactionTimestamps.isEmpty()) {
break;
}
commitTimestamp = committedTransactionTimestamps.getFirst();
if (commitTimestamp < timestamp) {
committedTransactionTimestamps.removeFirst();
actions = (Object[]) committedTransactions.removeFirst();
} else {
break;
}
}
mergeTransaction(session, actions, 0, actions.length,
commitTimestamp);
rowActionMapRemoveTransaction(actions, 0, actions.length, true);
}
}
/**
* merge a transaction committed at a given timestamp.
*/
void mergeTransaction(Session session, Object[] list, int start,
int limit, long timestamp) {
for (int i = start; i < limit; i++) {
RowAction rowact = (RowAction) list[i];
if (rowact == null || rowact.type == RowActionBase.ACTION_NONE
|| rowact.type == RowActionBase.ACTION_DELETE_FINAL) {
continue;
}
Row row = rowact.memoryRow;
if (row == null) {
PersistentStore store =
rowact.session.sessionData.getRowStore(rowact.table);
row = (Row) store.get(rowact.getPos(), false);
}
if (row == null) {
continue;
}
synchronized (row) {
rowact.mergeToTimestamp(row, timestamp);
}
}
}
/**
* gets the next timestamp for an action
*/
long nextChangeTimestamp() {
return globalChangeTimestamp.incrementAndGet();
}
public void beginTransaction(Session session) {
synchronized (liveTransactionTimestamps) {
session.actionTimestamp = nextChangeTimestamp();
session.transactionTimestamp = session.actionTimestamp;
session.isTransaction = true;
liveTransactionTimestamps.addLast(session.actionTimestamp);
try {
if (mvcc) {
database.logger.writeToLog(
session, session.getStartTransactionSQL());
}
} catch (HsqlException e) {}
}
}
/**
* add session to the end of queue when a transaction starts
* (depending on isolation mode)
*/
public void beginAction(Session session, Statement cs) {
synchronized (liveTransactionTimestamps) {
session.actionTimestamp = nextChangeTimestamp();
if (!session.isTransaction) {
session.transactionTimestamp = session.actionTimestamp;
session.isTransaction = true;
liveTransactionTimestamps.addLast(session.actionTimestamp);
try {
if (this.mvcc) {
database.logger.writeToLog(
session, session.getStartTransactionSQL());
}
} catch (HsqlException e) {}
}
}
if (session.isReadOnly()) {
return;
}
if (!mvcc) {
if (session.hasLocks()) {
return;
}
try {
writeLock.lock();
boolean canProceed = beginActionTPL(session, cs);
if (!canProceed) {
session.abortTransaction = true;
}
/* debug 190
if (!canProceed) {
System.out.println("******* cannot start");
}
// debug 190 */
} finally {
writeLock.unlock();
}
}
}
void endTransactionTPL(Session session) {
int unlockedCount = 0;
if (session.isReadOnly()) {
return;
}
unlockTablesTPL(session);
if (session.waitingSessions.isEmpty()) {
return;
}
for (int i = 0; i < session.waitingSessions.size(); i++) {
Session current = (Session) session.waitingSessions.get(i);
current.tempUnlocked = false;
long count = current.latch.getCount();
if (count == 1) {
boolean canProceed = setWaitedSessionsTPL(current,
current.currentStatement);
if (!canProceed) {
current.abortTransaction = true;
}
if (current.tempSet.isEmpty()) {
lockTablesTPL(current, current.currentStatement);
current.tempUnlocked = true;
unlockedCount++;
}
}
}
if (unlockedCount > 0) {
/* debug 190
if (unlockedCount > 1) {
System.out.println("*********** multiple unlocked");
}
// debug 190 */
for (int i = 0; i < session.waitingSessions.size(); i++) {
Session current = (Session) session.waitingSessions.get(i);
if (!current.tempUnlocked) {
boolean canProceed = setWaitedSessionsTPL(current,
current.currentStatement);
// this can introduce additional waits for the sessions
if (!canProceed) {
current.abortTransaction = true;
}
/* debug 190
if (current.tempSet.isEmpty()) {
System.out.println("*********** additional unlocked");
// shouldn't get here
}
// debug 190 */
}
}
}
for (int i = 0; i < session.waitingSessions.size(); i++) {
Session current = (Session) session.waitingSessions.get(i);
setWaitingSessionTPL(current);
}
session.tempSet.clear();
session.waitingSessions.clear();
}
boolean beginActionTPL(Session session, Statement cs) {
if (session.isReadOnly()) {
return true;
}
boolean canProceed = setWaitedSessionsTPL(session, cs);
if (canProceed) {
if (session.tempSet.isEmpty()) {
lockTablesTPL(session, cs);
// we dont set other sessions that would now be waiting for this one too
} else {
setWaitingSessionTPL(session);
}
return true;
}
return false;
}
boolean setWaitedSessionsTPL(Session session, Statement cs) {
session.tempSet.clear();
if (cs == null || session.abortTransaction) {
return true;
}
HsqlName[] nameList = cs.getTableNamesForWrite();
for (int i = 0; i < nameList.length; i++) {
HsqlName name = nameList[i];
if (name.schema == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
Session holder = (Session) tableWriteLocks.get(name);
if (holder != null && holder != session) {
session.tempSet.add(holder);
}
Iterator it = tableReadLocks.get(name);
while (it.hasNext()) {
holder = (Session) it.next();
if (holder != session) {
session.tempSet.add(holder);
}
}
}
nameList = cs.getTableNamesForRead();
for (int i = 0; i < nameList.length; i++) {
HsqlName name = nameList[i];
if (name.schema == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
Session holder = (Session) tableWriteLocks.get(name);
if (holder != null && holder != session) {
session.tempSet.add(holder);
}
}
for (int i = 0; i < session.waitingSessions.size(); i++) {
Session current = (Session) session.waitingSessions.get(i);
if (session.tempSet.contains(current)) {
session.tempSet.clear();
return false;
}
}
return true;
}
void setWaitingSessionTPL(Session session) {
int count = session.tempSet.size();
for (int i = 0; i < count; i++) {
Session current = (Session) session.tempSet.get(i);
current.waitingSessions.add(session);
}
session.tempSet.clear();
session.latch.setCount(count);
}
void lockTablesTPL(Session session, Statement cs) {
if (cs == null || session.abortTransaction) {
return;
}
HsqlName[] nameList = cs.getTableNamesForWrite();
for (int i = 0; i < nameList.length; i++) {
HsqlName name = nameList[i];
if (name.schema == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
tableWriteLocks.put(name, session);
}
nameList = cs.getTableNamesForRead();
for (int i = 0; i < nameList.length; i++) {
HsqlName name = nameList[i];
if (name.schema == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
tableReadLocks.put(name, session);
}
}
void unlockTablesTPL(Session session) {
Iterator it = tableWriteLocks.values().iterator();
while (it.hasNext()) {
Session s = (Session) it.next();
if (s == session) {
it.setValue(null);
}
}
it = tableReadLocks.values().iterator();
while (it.hasNext()) {
Session s = (Session) it.next();
if (s == session) {
it.remove();
}
}
}
/**
* remove session from queue when a transaction ends
* and expire any committed transactions
* that are no longer required. remove transactions ended before the first
* timestamp in liveTransactionsSession queue
*/
void endTransaction(Session session) {
try {
writeLock.lock();
long timestamp = session.transactionTimestamp;
synchronized (liveTransactionTimestamps) {
session.isTransaction = false;
int index = liveTransactionTimestamps.indexOf(timestamp);
liveTransactionTimestamps.remove(index);
}
mergeExpiredTransactions(session);
} finally {
writeLock.unlock();
}
}
long getFirstLiveTransactionTimestamp() {
synchronized (liveTransactionTimestamps) {
if (liveTransactionTimestamps.isEmpty()) {
return Long.MAX_VALUE;
}
return liveTransactionTimestamps.get(0);
}
}
// functional unit - list actions and translate id's
/**
* Return an array of all row actions sorted by System Change No.
*/
RowAction[] getRowActionList() {
try {
writeLock.lock();
Session[] sessions = database.sessionManager.getAllSessions();
int[] tIndex = new int[sessions.length];
RowAction[] rowActions;
int rowActionCount = 0;
{
int actioncount = 0;
for (int i = 0; i < sessions.length; i++) {
actioncount += sessions[i].getTransactionSize();
}
rowActions = new RowAction[actioncount];
}
while (true) {
boolean found = false;
long minChangeNo = Long.MAX_VALUE;
int sessionIndex = 0;
// find the lowest available SCN across all sessions
for (int i = 0; i < sessions.length; i++) {
int tSize = sessions[i].getTransactionSize();
if (tIndex[i] < tSize) {
RowAction current =
(RowAction) sessions[i].rowActionList.get(
tIndex[i]);
if (current.actionTimestamp < minChangeNo) {
minChangeNo = current.actionTimestamp;
sessionIndex = i;
}
found = true;
}
}
if (!found) {
break;
}
HsqlArrayList currentList =
sessions[sessionIndex].rowActionList;
for (; tIndex[sessionIndex] < currentList.size(); ) {
RowAction current =
(RowAction) currentList.get(tIndex[sessionIndex]);
// if the next change no is in this session, continue adding
if (current.actionTimestamp == minChangeNo + 1) {
minChangeNo++;
}
if (current.actionTimestamp == minChangeNo) {
rowActions[rowActionCount++] = current;
tIndex[sessionIndex]++;
} else {
break;
}
}
}
return rowActions;
} finally {
writeLock.unlock();
}
}
/**
* Return a lookup of all row ids for cached tables in transactions.
* For auto-defrag, as currently there will be no RowAction entries
* at the time of defrag.
*/
public DoubleIntIndex getTransactionIDList() {
writeLock.lock();
try {
DoubleIntIndex lookup = new DoubleIntIndex(10, false);
lookup.setKeysSearchTarget();
Iterator it = this.rowActionMap.keySet().iterator();
for (; it.hasNext(); ) {
lookup.addUnique(it.nextInt(), 0);
}
return lookup;
} finally {
writeLock.unlock();
}
}
/**
* Convert row ID's for cached table rows in transactions
*/
public void convertTransactionIDs(DoubleIntIndex lookup) {
writeLock.lock();
try {
RowAction[] list = new RowAction[rowActionMap.size()];
Iterator it = this.rowActionMap.values().iterator();
for (int i = 0; it.hasNext(); i++) {
list[i] = (RowAction) it.next();
}
rowActionMap.clear();
for (int i = 0; i < list.length; i++) {
int pos = lookup.lookupFirstEqual(list[i].getPos());
list[i].setPos(pos);
rowActionMap.put(pos, list[i]);
}
} finally {
writeLock.unlock();
}
}
//
void logTransaction(Object[] list, int size) {}
void unexpectedException(String message) {}
public void finalize() {}
}