ElementHolder<E, K, V>
CacheHolder<E, K, V>
MemoryHolder<E, K, V>
NodeCacheHolder<K, V> ->
CacheHolder<NodeValue<K, V>, K, V>
LeafCacheHolder>K, V> ->
CacheHolder<LeafValue<K, V>, K, V>
ValueCacheHolder<K, V> ->
CacheHolder<SingleValue<V>, K, V>
NodeMemoryHolder<K, V> ->
MemoryHolder<NodeValue<K, V>, K, V>
LeafMemoryHolder<K, V> ->
MemoryHolder<LeafValue<K, V>, K, V>
ValueMemoryHolder<K, V> ->
MemoryHolder<SingleValue<V>, K, V>
MultipleValueCacheHolder<K, V> ->
CacheHolder<BTreeValue<V>, K, V>
MultipleValueMemoryHolder<K, V> ->
MemoryHolder<BTreeValue<V>, K, V>