[infinispan-dev] How to get key ID passivated into DB

Vitalii Chepeliuk vchepeli at redhat.com
Fri Aug 9 09:57:39 EDT 2013


Hi all! I have a question about entry passivation into DB, concretly this class LockSupportCacheStore and method store
  @Override
   public final void store(InternalCacheEntry ed) throws CacheLoaderException {
      if (trace) {
         log.tracef("store(%s)", ed);
      }
      if (ed == null) {
        return;
      }
      if (ed.canExpire() && ed.isExpired(timeService.wallClockTime())) {
         if (containsKey(ed.getKey())) {
            if (trace) {
               log.tracef("Entry %s is expired!  Removing!", ed);
            }
            remove(ed.getKey());
         } else {
            if (trace) {
               log.tracef("Entry %s is expired!  Not doing anything.", ed);
            }
         }
         return;
      }

      L keyHashCode = getLockFromKey(ed.getKey()); <<< here key is generated like ed.getKey().hashCode() & 0xfffffc00; 
      lockForWriting(keyHashCode);
      try {
         storeLockSafe(ed, keyHashCode); <<< here it should be stored into Bucket and then stored in DB
      } finally {
         unlock(keyHashCode);
      }
      if (trace) {
         log.tracef("exit store(%s)", ed);
      }
   }
When I use RemoteCacheManager and RemoteCache I am putting entries into cache
   cache.put("key1", "v1");
   cache.put("key2", "v2");
   cache.put("key3", "v3");
Then 2 entries are passivated and stored in DB 
ID                                     DATA									VERSION
183713792	0301fe032a01034c422b21033e286d7942657374506572736f6e616c4b657957686963684861734e657665724265656e426574746572420521033e02763203620003630000000000000002	-1
23486464	0301fe032a01034c420721033e046b657931420521033e02763103620003630000000000000001					                                        -1
IDs are generated from method above and 
byte[] keyBytes = marshaller.objectToByteBuffer(key, 64); <<< data are marshalled
long keyID = ByteArrayEquivalence.INSTANCE.hashCode(keyBytes) & 0xfffffc00 //computation taken from BucketBasedCacheStore << this does not work for me
And next step I'd like to retrieve data from DB
SELECT ID, DATA FROM JDBC_BINARY_DEFAULT WHERE ID=keyID
But in method
   @Override
   public Integer getLockFromKey(Object key) {
       return key.hashCode() & 0xfffffc00; <<< here should be used Arrays.hashCode((byte[])key)  & 0xfffffc00), if key is represented as byte array, or Used ByteArrayEquivalence instead of simple byte array(byte[]) as argument
   }


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