/**
* Do a group update for data associated with a given key
*
* @param accessor accessor with the ability to pull from the current data
* @param options see {@link AccessOption}
* @param key the data identifier
* @param record the data to be merged in
* @return true if successful, false otherwise
*/
public boolean commit(
BaseDataAccessor<ZNRecord> accessor, int options, String key, ZNRecord record) {
Queue queue = getQueue(key);
Entry entry = new Entry(key, record);
queue._pending.add(entry);
while (!entry._sent.get()) {
if (queue._running.compareAndSet(null, Thread.currentThread())) {
ArrayList<Entry> processed = new ArrayList<Entry>();
try {
if (queue._pending.peek() == null) return true;
// remove from queue
Entry first = queue._pending.poll();
processed.add(first);
String mergedKey = first._key;
// ZNRecord merged = _cache.get(mergedKey);
ZNRecord merged = null;
try {
// accessor will fallback to zk if not found in cache
merged = accessor.get(mergedKey, null, options);
} catch (ZkNoNodeException e) {
// OK.
}
/**
* If the local cache does not contain a value, need to check if there is a value in ZK;
* use it as initial value if exists
*/
if (merged == null) {
// ZNRecord valueOnZk = null;
// try
// {
// valueOnZk = accessor.get(mergedKey, null, 0);
// }
// catch(Exception e)
// {
// LOG.info(e);
// }
// if(valueOnZk != null)
// {
// merged = valueOnZk;
// merged.merge(first._record);
// }
// else // Zk path has null data. use the first record as initial record.
{
merged = new ZNRecord(first._record);
}
} else {
merged.merge(first._record);
}
Iterator<Entry> it = queue._pending.iterator();
while (it.hasNext()) {
Entry ent = it.next();
if (!ent._key.equals(mergedKey)) continue;
processed.add(ent);
merged.merge(ent._record);
// System.out.println("After merging:" + merged);
it.remove();
}
// System.out.println("size:"+ processed.size());
accessor.set(mergedKey, merged, options);
// accessor.set(mergedKey, merged, BaseDataAccessor.Option.PERSISTENT);
// _cache.put(mergedKey, merged);
} finally {
queue._running.set(null);
for (Entry e : processed) {
synchronized (e) {
e._sent.set(true);
e.notify();
}
}
}
} else {
synchronized (entry) {
try {
entry.wait(10);
} catch (InterruptedException e) {
e.printStackTrace();
return false;
}
}
}
}
return true;
}
