Пример #1
0
  public void removeFriends(String from_uname, List<String> to_unames) {

    Mutator<String> mutator = cassandra.getMutator();
    for (String uname : to_unames) {
      mutator
          .addDeletion(from_uname, FRIENDS, uname, SE)
          .addDeletion(uname, FOLLOWERS, from_uname, SE);
      mutator.decrementCounter(from_uname, MISC_COUNTS, "friends", 1);
      mutator.decrementCounter(uname, MISC_COUNTS, "followers", 1);
    }
    mutator.execute();
  }
Пример #2
0
 /**
  * Decrement counter by 1
  *
  * @param rawID raw name
  * @param columnFamily column family name
  * @param columnName name of column
  * @param keyspace keyspace
  * @throws CassandraDataAccessException
  */
 public static void decrementCounter(
     String columnName, String columnFamily, String rawID, Keyspace keyspace, long decrementBy)
     throws CassandraDataAccessException {
   try {
     Mutator<String> mutator = HFactory.createMutator(keyspace, StringSerializer.get());
     mutator.decrementCounter(rawID, columnFamily, columnName, decrementBy);
     mutator.execute();
   } catch (Exception e) {
     throw new CassandraDataAccessException("Error while accessing:" + columnFamily, e);
   }
 }
Пример #3
0
  public void removeCounterRow(K key) {
    SliceCounterQuery<K, N> query =
        HFactory.createCounterSliceQuery(keyspace, keySerializer, columnNameSerializer)
            .setColumnFamily(columnFamily)
            .setKey(key);

    AchillesCounterSliceIterator<K, N> iterator =
        new AchillesCounterSliceIterator<K, N>(
            policy, columnFamily, query, (N) null, (N) null, false, DEFAULT_LENGTH);

    Mutator<K> mutator = HFactory.createMutator(keyspace, keySerializer);
    while (iterator.hasNext()) {
      HCounterColumn<N> counterCol = iterator.next();
      mutator.decrementCounter(key, columnFamily, counterCol.getName(), counterCol.getValue());
    }
    this.executeMutator(mutator);
  }
Пример #4
0
 public void removeCounter(K key, N name) {
   Mutator<K> mutator = buildMutator();
   Long currentValue = this.getCounterValue(key, name);
   mutator.decrementCounter(key, columnFamily, name, currentValue);
   this.executeMutator(mutator);
 }