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Berkeley DB version 4.4.20 |
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java.lang.Object com.sleepycat.collections.StoredContainer
A abstract base class for all stored collections and maps. This class
provides implementations of methods that are common to the Collection
and the Map
interfaces, namely
clear()
, isEmpty()
and size()
.
Note that this class does not conform to the standard Java collections interface in the following ways:
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, this class provides the following methods for stored collections only. Note that the use of these methods is not compatible with the standard Java collections interface.
isWriteAllowed()
isSecondary()
isOrdered()
areDuplicatesAllowed()
areDuplicatesOrdered()
areKeysRenumbered()
getCursorConfig()
isTransactional()
Method Summary | |
boolean |
areDuplicatesAllowed()
Returns whether duplicate keys are allowed in this container. |
boolean |
areDuplicatesOrdered()
Returns whether duplicate keys are allowed and sorted by element value. |
boolean |
areKeysRenumbered()
Returns whether keys are renumbered when insertions and deletions occur. |
void |
clear()
Removes all mappings or elements from this map or collection (optional operation). |
CursorConfig |
getCursorConfig()
Returns the cursor configuration that is used for all operations performed via this container. |
boolean |
isDirtyRead()
Deprecated. This method has been replaced by getCursorConfig() .
CursorConfig.isReadUncommitted may be called to determine
whether dirty-read is enabled. |
boolean |
isDirtyReadAllowed()
Deprecated. This method is deprecated with no replacement in this class. In the DB product, DatabaseConfig.getReadUncommitted may be
called. |
boolean |
isEmpty()
Returns true if this map or collection contains no mappings or elements. |
boolean |
isOrdered()
Returns whether keys are ordered in this container. |
boolean |
isSecondary()
Returns whether this container is a view on a secondary database rather than directly on a primary database. |
boolean |
isTransactional()
Returns whether the databases underlying this container are transactional. |
boolean |
isWriteAllowed()
Returns true if this is a read-write container or false if this is a read-only container. |
int |
size()
Always throws UnsupportedOperationException. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Method Detail |
public final boolean isWriteAllowed()
Map
or
Collection
interfaces.
public final CursorConfig getCursorConfig()
CursorConfig.getReadUncommitted
returns
true, data will be read that is modified but not committed.
This method does not exist in the standard Map
or
Collection
interfaces.
public final boolean isDirtyReadAllowed()
DatabaseConfig.getReadUncommitted
may be
called.
StoredCollections
methods.
This method does not exist in the standard Map
or
Collection
interfaces.
public final boolean isDirtyRead()
getCursorConfig()
.
CursorConfig.isReadUncommitted
may be called to determine
whether dirty-read is enabled.
public final boolean isTransactional()
Map
or
Collection
interfaces.
public final boolean areDuplicatesAllowed()
Map
or
Collection
interfaces.
Note that the JE product only supports BTREE databases.
public final boolean areDuplicatesOrdered()
Map
or
Collection
interfaces.
Note that the JE product only supports BTREE databases, and duplicates are always sorted.
public final boolean areKeysRenumbered()
Map
or
Collection
interfaces.
Note that the JE product does not support RECNO databases, and therefore keys are never renumbered.
public final boolean isOrdered()
Map
or
Collection
interfaces.
Note that the JE product only support BTREE databases, and therefore keys are always ordered.
public final boolean isSecondary()
Map
or
Collection
interfaces.
public int size()
Collection.size()
and
Map.size()
interfaces.
UnsupportedOperationException
- unconditionally.public boolean isEmpty()
Collection.isEmpty()
and
Map.isEmpty()
interfaces.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.public void clear()
Collection.clear()
and
Map.clear()
interfaces.
UnsupportedOperationException
- if the container is read-only.
RuntimeExceptionWrapper
- if a DatabaseException
is thrown.
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Berkeley DB version 4.4.20 |
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