protected void destruct() {
if (lockMgr != null) {
try {
lockMgr.close();
} catch (LockException e) {
// Not much I can do about it.
LOG.warn("Got exception when closing lock manager " + e.getMessage());
}
}
}
@Override
public HiveLockManager getLockManager() throws LockException {
if (lockMgr == null) {
boolean supportConcurrency = conf.getBoolVar(HiveConf.ConfVars.HIVE_SUPPORT_CONCURRENCY);
if (supportConcurrency) {
String lockMgrName = conf.getVar(HiveConf.ConfVars.HIVE_LOCK_MANAGER);
if ((lockMgrName == null) || (lockMgrName.isEmpty())) {
throw new LockException(ErrorMsg.LOCKMGR_NOT_SPECIFIED.getMsg());
}
try {
LOG.info("Creating lock manager of type " + lockMgrName);
lockMgr =
(HiveLockManager) ReflectionUtils.newInstance(conf.getClassByName(lockMgrName), conf);
lockMgr.setContext(new HiveLockManagerCtx(conf));
} catch (Exception e) {
// set hiveLockMgr to null just in case this invalid manager got set to
// next query's ctx.
if (lockMgr != null) {
try {
lockMgr.close();
} catch (LockException e1) {
// nothing can do here
}
lockMgr = null;
}
throw new LockException(ErrorMsg.LOCKMGR_NOT_INITIALIZED.getMsg() + e.getMessage());
}
} else {
LOG.info("Concurrency mode is disabled, not creating a lock manager");
return null;
}
}
// Force a re-read of the configuration file. This is done because
// different queries in the session may be using the same lock manager.
lockMgr.refresh();
return lockMgr;
}
@Override
public void acquireLocks(QueryPlan plan, Context ctx, String username) throws LockException {
// Make sure we've built the lock manager
getLockManager();
// If the lock manager is still null, then it means we aren't using a
// lock manager
if (lockMgr == null) return;
List<HiveLockObj> lockObjects = new ArrayList<HiveLockObj>();
// Sort all the inputs, outputs.
// If a lock needs to be acquired on any partition, a read lock needs to be acquired on all
// its parents also
for (ReadEntity input : plan.getInputs()) {
if (!input.needsLock()) {
continue;
}
LOG.debug("Adding " + input.getName() + " to list of lock inputs");
if (input.getType() == ReadEntity.Type.DATABASE) {
lockObjects.addAll(
getLockObjects(plan, input.getDatabase(), null, null, HiveLockMode.SHARED));
} else if (input.getType() == ReadEntity.Type.TABLE) {
lockObjects.addAll(getLockObjects(plan, null, input.getTable(), null, HiveLockMode.SHARED));
} else {
lockObjects.addAll(
getLockObjects(plan, null, null, input.getPartition(), HiveLockMode.SHARED));
}
}
for (WriteEntity output : plan.getOutputs()) {
HiveLockMode lockMode = getWriteEntityLockMode(output);
if (lockMode == null) {
continue;
}
LOG.debug("Adding " + output.getName() + " to list of lock outputs");
List<HiveLockObj> lockObj = null;
if (output.getType() == WriteEntity.Type.DATABASE) {
lockObjects.addAll(getLockObjects(plan, output.getDatabase(), null, null, lockMode));
} else if (output.getTyp() == WriteEntity.Type.TABLE) {
lockObj = getLockObjects(plan, null, output.getTable(), null, lockMode);
} else if (output.getTyp() == WriteEntity.Type.PARTITION) {
lockObj = getLockObjects(plan, null, null, output.getPartition(), lockMode);
}
// In case of dynamic queries, it is possible to have incomplete dummy partitions
else if (output.getTyp() == WriteEntity.Type.DUMMYPARTITION) {
lockObj = getLockObjects(plan, null, null, output.getPartition(), HiveLockMode.SHARED);
}
if (lockObj != null) {
lockObjects.addAll(lockObj);
ctx.getOutputLockObjects().put(output, lockObj);
}
}
if (lockObjects.isEmpty() && !ctx.isNeedLockMgr()) {
return;
}
dedupLockObjects(lockObjects);
List<HiveLock> hiveLocks = lockMgr.lock(lockObjects, false);
if (hiveLocks == null) {
throw new LockException(ErrorMsg.LOCK_CANNOT_BE_ACQUIRED.getMsg());
} else {
ctx.setHiveLocks(hiveLocks);
}
}
