| Class | Description | 
|---|---|
| AbstractPackedMap<K,V> | An object that maps keys to values. | 
| AbstractWeakPackedMap<K,V> | |
| IdentityPackedMap<K,V> | This class implements the  AbstractPackedMapclass, using reference-equality when comparing keys. | 
| PackedMap<K,V> | This class implements the  AbstractPackedMapclass, using object-equality when comparing keys. | 
| WeakIdentityPackedMap<K,V> | |
| WeakPackedMap<K,V> |