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java.lang.Object com.sleepycat.collections.StoredContainer com.sleepycat.collections.StoredCollection com.sleepycat.collections.StoredKeySet com.sleepycat.collections.StoredSortedKeySet
The SortedSet 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.
Note that this class does not conform to the standard Java collections interface in the following ways:
StoredContainer.size()
method always throws
UnsupportedOperationException
because, for performance reasons,
databases do not maintain their total record count.StoredIterator.close()
or StoredIterator.close(java.util.Iterator)
to release the underlying database cursor resources.In addition to the standard SortedSet methods, this class provides the following methods for stored sorted sets only. Note that the use of these methods is not compatible with the standard Java collections interface.
Constructor Summary | |
StoredSortedKeySet(Database database,
EntryBinding keyBinding,
boolean writeAllowed)
Creates a sorted key set view of a Database . |
Method Summary | |
Comparator |
comparator()
Returns null since comparators are not supported. |
Object |
first()
Returns the first (lowest) element currently in this sorted set. |
SortedSet |
headSet(Object toKey)
Returns a view of the portion of this sorted set whose elements are strictly less than toKey. |
SortedSet |
headSet(Object toKey,
boolean toInclusive)
Returns a view of the portion of this sorted set whose elements are strictly less than toKey, optionally including toKey. |
Object |
last()
Returns the last (highest) element currently in this sorted set. |
SortedSet |
subSet(Object fromKey,
boolean fromInclusive,
Object toKey,
boolean toInclusive)
Returns a view of the portion of this sorted set whose elements are strictly greater than fromKey and strictly less than toKey, optionally including fromKey and toKey. |
SortedSet |
subSet(Object fromKey,
Object toKey)
Returns a view of the portion of this sorted set whose elements range from fromKey, inclusive, to toKey, exclusive. |
SortedSet |
tailSet(Object fromKey)
Returns a view of the portion of this sorted set whose elements are greater than or equal to fromKey. |
SortedSet |
tailSet(Object fromKey,
boolean fromInclusive)
Returns a view of the portion of this sorted set whose elements are strictly greater than fromKey, optionally including fromKey. |
Methods inherited from class com.sleepycat.collections.StoredKeySet |
add, contains, remove |
Methods inherited from class com.sleepycat.collections.StoredCollection |
addAll, containsAll, equals, hashCode, iterator, iterator, join, removeAll, retainAll, toArray, toArray, toList, toString |
Methods inherited from class com.sleepycat.collections.StoredContainer |
areDuplicatesAllowed, areDuplicatesOrdered, areKeysRenumbered, clear, getCursorConfig, isDirtyRead, isDirtyReadAllowed, isEmpty, isOrdered, isSecondary, isTransactional, isWriteAllowed, size |
Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
Methods inherited from interface java.util.Set |
add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray |
Constructor Detail |
public StoredSortedKeySet(Database database, EntryBinding keyBinding, boolean writeAllowed)
Database
.
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.
IllegalArgumentException
- if formats are not consistently
defined or a parameter is invalid.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.Method Detail |
public Comparator comparator()
Comparable
interface or not.
This method does not conform to the SortedSet.comparator()
interface.
comparator
in interface SortedSet
public Object first()
SortedSet.first()
interface.
first
in interface SortedSet
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public Object last()
SortedSet.last()
interface.
last
in interface SortedSet
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet headSet(Object toKey)
SortedSet.headSet(java.lang.Object)
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
headSet
in interface SortedSet
toKey
- is the upper bound.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet headSet(Object toKey, boolean toInclusive)
SortedSet
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
toKey
- is the upper bound.toInclusive
- is true to include toKey.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet tailSet(Object fromKey)
SortedSet.tailSet(java.lang.Object)
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
tailSet
in interface SortedSet
fromKey
- is the lower bound.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet tailSet(Object fromKey, boolean fromInclusive)
SortedSet
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
fromKey
- is the lower bound.fromInclusive
- is true to include fromKey.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet subSet(Object fromKey, Object toKey)
SortedSet.subSet(java.lang.Object, java.lang.Object)
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
subSet
in interface SortedSet
fromKey
- is the lower bound.toKey
- is the upper bound.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public SortedSet subSet(Object fromKey, boolean fromInclusive, Object toKey, boolean toInclusive)
SortedSet
interface.
Note that the return value is a StoredCollection and must be treated as such; for example, its iterators must be explicitly closed.
fromKey
- is the lower bound.fromInclusive
- is true to include fromKey.toKey
- is the upper bound.toInclusive
- is true to include toKey.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.
|
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