private boolean blockExistsInCache( int currentBlockNumber )
		{
			boolean exists = false;
			int block = -1;
			for( int i = 0 ; i < cacheBlocks.length && !exists ; i ++ )
			{
				if( cacheBlocks[i].getBlockState() != CacheBlock.State.EMPTY )
				{
					int cacheBlockNumber = cacheBlocks[i].getBlockNumber( );
					if( cacheBlockNumber == currentBlockNumber )
					{
						exists = true;
						block = i;
					}
				}
			}
			if( exists )
			{
				this.currentBlockNumber.set( block );
			}
			return exists;
		}