public Object getNextValue(Sequence sequence, AbstractSession writeSession) {
String seqName = sequence.getName();
if (sequence.getPreallocationSize() > 1) {
Queue sequencesForName = getPreallocationHandler().getPreallocated(seqName);
// First try to get the next sequence value without locking.
Object sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
// Sequences are empty, so must lock and allocate next batch of sequences.
acquireLock(seqName);
try {
sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
Vector sequences = sequence.getGeneratedVector(null, writeSession);
// Remove the first value before adding to the global cache to ensure this thread gets
// one.
sequenceValue = sequences.remove(0);
// copy remaining values to global cache.
getPreallocationHandler().setPreallocated(seqName, sequences);
logDebugPreallocation(seqName, sequenceValue, sequences);
} finally {
releaseLock(seqName);
}
return sequenceValue;
} else {
// preallocation size is 1 - just return the first (and only) element of the allocated
// vector.
return sequence.getGeneratedVector(null, writeSession).firstElement();
}
}
/** Release any locally allocated sequence back to the global sequence pool. */
void afterCommitInternal(Map localSequences, Accessor accessor) {
Iterator it = localSequences.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
String seqName = (String) entry.getKey();
Vector localSequenceForName = (Vector) entry.getValue();
if (!localSequenceForName.isEmpty()) {
getPreallocationHandler().setPreallocated(seqName, localSequenceForName);
// clear all localSequencesForName
localSequenceForName.clear();
}
}
if (accessor != null) {
getOwnerSession()
.log(
SessionLog.FINEST,
SessionLog.SEQUENCING,
"sequencing_afterTransactionCommitted",
null,
accessor);
} else {
getOwnerSession()
.log(
SessionLog.FINEST,
SessionLog.SEQUENCING,
"sequencing_afterTransactionCommitted",
null);
}
}
protected void logDebugPreallocation(
String seqName, Object firstSequenceValue, Vector sequences) {
if (getOwnerSession().shouldLog(SessionLog.FINEST, SessionLog.SEQUENCING)) {
// the first value has been already removed from sequences vector
Object[] args = {
seqName, new Integer(sequences.size() + 1), firstSequenceValue, sequences.lastElement()
};
getOwnerSession()
.log(SessionLog.FINEST, SessionLog.SEQUENCING, "sequencing_preallocation", args);
}
}
protected void logDebugLocalPreallocation(
AbstractSession writeSession, String seqName, Vector sequences, Accessor accessor) {
if (writeSession.shouldLog(SessionLog.FINEST, SessionLog.SEQUENCING)) {
Object[] args = {
seqName, new Integer(sequences.size()), sequences.firstElement(), sequences.lastElement()
};
writeSession.log(
SessionLog.FINEST,
SessionLog.SEQUENCING,
"sequencing_localPreallocation",
args,
accessor);
}
}
protected void initializeStates() {
states = new State[NUMBER_OF_STATES];
Iterator itConnectedSequences = connectedSequences.iterator();
while (itConnectedSequences.hasNext()) {
Sequence sequence = (Sequence) itConnectedSequences.next();
State state = getState(sequence.shouldUsePreallocation(), sequence.shouldUseTransaction());
if (state == null) {
createState(sequence.shouldUsePreallocation(), sequence.shouldUseTransaction());
}
}
}
protected void logDebugSequencingConnected() {
Vector[] sequenceVectors = new Vector[NUMBER_OF_STATES];
Iterator itConnectedSequences = connectedSequences.iterator();
while (itConnectedSequences.hasNext()) {
Sequence sequence = (Sequence) itConnectedSequences.next();
int stateId = getStateId(sequence.shouldUsePreallocation(), sequence.shouldUseTransaction());
Vector v = sequenceVectors[stateId];
if (v == null) {
v = new Vector();
sequenceVectors[stateId] = v;
}
v.addElement(sequence);
}
for (int i = 0; i < NUMBER_OF_STATES; i++) {
Vector v = sequenceVectors[i];
if (v != null) {
getOwnerSession()
.log(SessionLog.FINEST, SessionLog.SEQUENCING, "sequencing_connected", states[i]);
for (int j = 0; j < v.size(); j++) {
Sequence sequence = (Sequence) v.elementAt(j);
Object[] args = {
sequence.getName(),
Integer.toString(sequence.getPreallocationSize()),
Integer.toString(sequence.getInitialValue())
};
getOwnerSession()
.log(SessionLog.FINEST, SessionLog.SEQUENCING, "sequence_without_state", args);
}
}
}
}
protected void onDisconnectAllSequences() {
RuntimeException exception = null;
// defaultSequence has to disconnect the last
for (int i = connectedSequences.size() - 1; i >= 0; i--) {
try {
Sequence sequenceToDisconnect = (Sequence) connectedSequences.elementAt(i);
sequenceToDisconnect.onDisconnect(getOwnerSession().getDatasourcePlatform());
} catch (RuntimeException ex) {
if (exception == null) {
exception = ex;
}
}
}
connectedSequences = null;
whenShouldAcquireValueForAll = UNDEFINED;
atLeastOneSequenceShouldUseTransaction = false;
atLeastOneSequenceShouldUsePreallocation = false;
if (exception != null) {
throw exception;
}
}
protected void onConnectAllSequences() {
connectedSequences = new Vector();
boolean shouldUseTransaction = false;
boolean shouldUsePreallocation = false;
boolean shouldAcquireValueAfterInsert = false;
Iterator descriptors = getOwnerSession().getDescriptors().values().iterator();
while (descriptors.hasNext()) {
ClassDescriptor descriptor = (ClassDescriptor) descriptors.next();
// Find root sequence, because inheritance needs to be resolved here.
// TODO: The way we initialize sequencing needs to be in line with descriptor init.
ClassDescriptor parentDescriptor = descriptor;
while (!parentDescriptor.usesSequenceNumbers() && parentDescriptor.isChildDescriptor()) {
ClassDescriptor newDescriptor =
getOwnerSession()
.getDescriptor(parentDescriptor.getInheritancePolicy().getParentClass());
// Avoid issue with error cases of self parent, or null parent.
if ((newDescriptor == null) || (newDescriptor == parentDescriptor)) {
break;
}
parentDescriptor = newDescriptor;
}
if (!parentDescriptor.usesSequenceNumbers()) {
continue;
}
String seqName = parentDescriptor.getSequenceNumberName();
Sequence sequence = getSequence(seqName);
if (sequence == null) {
sequence = new DefaultSequence(seqName);
getOwnerSession().getDatasourcePlatform().addSequence(sequence);
}
// PERF: Initialize the sequence, this avoid having to look it up every time.
descriptor.setSequence(sequence);
if (connectedSequences.contains(sequence)) {
continue;
}
try {
if (sequence instanceof DefaultSequence
&& !connectedSequences.contains(getDefaultSequence())) {
getDefaultSequence().onConnect(getOwnerSession().getDatasourcePlatform());
connectedSequences.add(0, getDefaultSequence());
shouldUseTransaction |= getDefaultSequence().shouldUseTransaction();
shouldUsePreallocation |= getDefaultSequence().shouldUsePreallocation();
shouldAcquireValueAfterInsert |= getDefaultSequence().shouldAcquireValueAfterInsert();
}
sequence.onConnect(getOwnerSession().getDatasourcePlatform());
connectedSequences.addElement(sequence);
shouldUseTransaction |= sequence.shouldUseTransaction();
shouldUsePreallocation |= sequence.shouldUsePreallocation();
shouldAcquireValueAfterInsert |= sequence.shouldAcquireValueAfterInsert();
} catch (RuntimeException ex) {
// defaultSequence has to disconnect the last
for (int i = connectedSequences.size() - 1; i >= 0; i--) {
try {
Sequence sequenceToDisconnect = (Sequence) connectedSequences.elementAt(i);
sequenceToDisconnect.onDisconnect(getOwnerSession().getDatasourcePlatform());
} catch (RuntimeException ex2) {
// ignore
}
}
connectedSequences = null;
throw ex;
}
}
if (shouldAcquireValueAfterInsert && !shouldUsePreallocation) {
whenShouldAcquireValueForAll = AFTER_INSERT;
} else if (!shouldAcquireValueAfterInsert && shouldUsePreallocation) {
whenShouldAcquireValueForAll = BEFORE_INSERT;
}
atLeastOneSequenceShouldUseTransaction = shouldUseTransaction;
atLeastOneSequenceShouldUsePreallocation = shouldUsePreallocation;
}
public Object getNextValue(Sequence sequence, AbstractSession writeSession) {
String seqName = sequence.getName();
if (sequence.getPreallocationSize() > 1) {
Queue sequencesForName = getPreallocationHandler().getPreallocated(seqName);
// First try to get the next sequence value without locking.
Object sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
// Sequences are empty, so must lock and allocate next batch of sequences.
acquireLock(seqName);
try {
sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
// note that accessor.getLogin().shouldUseExternalTransactionController()
// should be set to false
Accessor accessor = getConnectionHandler().acquireAccessor();
try {
accessor.beginTransaction(writeSession);
try {
Vector sequences = sequence.getGeneratedVector(accessor, writeSession);
accessor.commitTransaction(writeSession);
// Remove the first value before adding to the global cache to ensure this thread gets
// one.
sequenceValue = sequences.remove(0);
// copy remaining values to global cache.
getPreallocationHandler().setPreallocated(seqName, sequences);
logDebugPreallocation(seqName, sequenceValue, sequences);
} catch (RuntimeException ex) {
try {
// make sure to rollback the transaction we've begun
accessor.rollbackTransaction(writeSession);
} catch (Exception rollbackException) {
// ignore rollback exception
}
// don't eat the original exception
throw ex;
}
} finally {
getConnectionHandler().releaseAccessor(accessor);
}
} finally {
releaseLock(seqName);
}
return sequenceValue;
} else {
// note that accessor.getLogin().shouldUseExternalTransactionController()
// should be set to false
Accessor accessor = getConnectionHandler().acquireAccessor();
try {
accessor.beginTransaction(writeSession);
try {
// preallocation size is 1 - just return the first (and only) element of the allocated
// vector.
Object sequenceValue =
sequence.getGeneratedVector(accessor, writeSession).firstElement();
accessor.commitTransaction(writeSession);
return sequenceValue;
} catch (RuntimeException ex) {
try {
// make sure to rollback the transaction we've begun
accessor.rollbackTransaction(writeSession);
} catch (Exception rollbackException) {
// ignore rollback exception
}
// don't eat the original exception
throw ex;
}
} finally {
getConnectionHandler().releaseAccessor(accessor);
}
}
}
/**
* Return the next sequence value. First check the global pool, if empty then allocate new
* sequences locally.
*/
public Object getNextValue(Sequence sequence, AbstractSession writeSession) {
String seqName = sequence.getName();
if (sequence.getPreallocationSize() > 1) {
Queue sequencesForName = getPreallocationHandler().getPreallocated(seqName);
// First grab the first sequence value without locking, a lock is only required if empty.
Object sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
// KeepLocked indicates whether the sequence lock should be kept for the whole duration of
// this method.
// Of course the lock should be released in any case when the method returns or throws an
// exception.
// This is only used if a sequence transaction was begun by the unit of work,
// and will be committed before the unit of work commit.
boolean keepLocked = false;
if (!getOwnerSession().getDatasourceLogin().shouldUseExternalTransactionController()
&& !writeSession.isInTransaction()) {
// To prevent several threads from simultaneously allocating a separate bunch of
// sequencing numbers each. With keepLocked==true the first thread locks out others
// until it copies the obtained sequence numbers to the global storage.
// Note that this optimization possible only in non-jts case when there is no transaction.
acquireLock(seqName);
try {
sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
writeSession.beginTransaction(); // write accessor is set in begin
keepLocked = true;
} finally {
if (!keepLocked) {
releaseLock(seqName);
}
}
}
Accessor accessor;
Vector localSequencesForName;
if (!keepLocked) {
writeSession.beginTransaction(); // write accessor is set in begin
}
try {
accessor = writeSession.getAccessor();
SequencingCallbackImpl seqCallbackImpl = getCallbackImpl(writeSession, accessor);
Map localSequences = seqCallbackImpl.getPreallocatedSequenceValues();
localSequencesForName = (Vector) localSequences.get(seqName);
if ((localSequencesForName == null) || localSequencesForName.isEmpty()) {
localSequencesForName = sequence.getGeneratedVector(null, writeSession);
localSequences.put(seqName, localSequencesForName);
logDebugLocalPreallocation(writeSession, seqName, localSequencesForName, accessor);
}
} catch (RuntimeException ex) {
if (keepLocked) {
releaseLock(seqName);
}
try {
// make sure to rollback the transaction we've begun
writeSession.rollbackTransaction();
} catch (Exception rollbackException) {
// ignore rollback exception
}
// don't eat the original exception
throw ex;
}
try {
try {
// commitTransaction may copy preallocated sequence numbers
// from localSequences to preallocationHandler: that happens
// if it isn't a nested transaction, and sequencingCallback.afterCommit
// method has been called.
// In this case:
// 1. localSequences corresponding to the accessor
// has been removed from accessorToPreallocated;
// 2. All its members are empty (therefore localSequenceForName is empty).
writeSession.commitTransaction();
} catch (DatabaseException ex) {
try {
// make sure to rollback the transaction we've begun
writeSession.rollbackTransaction();
} catch (Exception rollbackException) {
// ignore rollback exception
}
// don't eat the original exception
throw ex;
}
if (!localSequencesForName.isEmpty()) {
// localSeqencesForName is not empty, that means
// sequencingCallback has not been called.
sequenceValue = localSequencesForName.remove(0);
return sequenceValue;
} else {
// localSeqencesForName is empty, that means
// sequencingCallback has been called.
sequenceValue = sequencesForName.poll();
if (sequenceValue != null) {
return sequenceValue;
}
return getNextValue(sequence, writeSession);
}
} finally {
if (keepLocked) {
releaseLock(seqName);
}
}
} else {
writeSession.beginTransaction();
try {
// preallocation size is 1 - just return the first (and only) element of the allocated
// vector.
Object sequenceValue = sequence.getGeneratedVector(null, writeSession).firstElement();
writeSession.commitTransaction();
return sequenceValue;
} catch (RuntimeException ex) {
try {
// make sure to rollback the transaction we've begun
writeSession.rollbackTransaction();
} catch (Exception rollbackException) {
// ignore rollback exception
}
// don't eat the original exception
throw ex;
}
}
}