com.sleepycat.collections

Class StoredKeySet

public class StoredKeySet extends StoredCollection implements Set

The Set returned by Map.keySet() and which can also be constructed directly if a Map is not needed. Since this collection is a set it only contains one element for each key, even when duplicates are allowed. Key set iterators are therefore particularly useful for enumerating the unique keys of a store or index that allows duplicates.
Constructor Summary
StoredKeySet(Database database, EntryBinding keyBinding, boolean writeAllowed)
Creates a key set view of a Database.
Method Summary
booleanadd(Object key)
Adds the specified key to this set if it is not already present (optional operation).
booleancontains(Object key)
Returns true if this set contains the specified key.
booleanremove(Object key)
Removes the specified key from this set if it is present (optional operation).

Constructor Detail

StoredKeySet

public StoredKeySet(Database database, EntryBinding keyBinding, boolean writeAllowed)
Creates a key set view of a Database.

Parameters: database is the Database underlying the new collection. keyBinding is the binding used to translate between key buffers and key objects. writeAllowed is true to create a read-write collection or false to create a read-only collection.

Throws: IllegalArgumentException if formats are not consistently defined or a parameter is invalid. RuntimeExceptionWrapper if a DatabaseException is thrown.

Method Detail

add

public boolean add(Object key)
Adds the specified key to this set if it is not already present (optional operation). When a key is added the value in the underlying data store will be empty. This method conforms to the Set#add interface.

Throws: UnsupportedOperationException if the collection is indexed, or if the collection is read-only. RuntimeExceptionWrapper if a DatabaseException is thrown.

contains

public boolean contains(Object key)
Returns true if this set contains the specified key. This method conforms to the Set#contains interface.

Throws: RuntimeExceptionWrapper if a DatabaseException is thrown.

remove

public boolean remove(Object key)
Removes the specified key from this set if it is present (optional operation). If duplicates are allowed, this method removes all duplicates for the given key. This method conforms to the Set#remove interface.

Throws: UnsupportedOperationException if the collection is read-only. RuntimeExceptionWrapper if a DatabaseException is thrown.