com.sleepycat.db
Class SecondaryCursor

java.lang.Object
  com.sleepycat.db.Cursor
      com.sleepycat.db.SecondaryCursor

public class SecondaryCursor

extends Cursor

A database cursor for a secondary database. Cursors are not thread safe and the application is responsible for coordinating any multithreaded access to a single cursor object.

Secondary cursors are returned by SecondaryDatabase.openCursor and SecondaryDatabase.openSecondaryCursor. The distinguishing characteristics of a secondary cursor are:

• Direct calls to put() methods on a secondary cursor are prohibited.
• The Cursor.delete() method of a secondary cursor will delete the primary record and as well as all its associated secondary records.
• Calls to all get methods will return the data from the associated primary database.
• Additional get method signatures are provided to return the primary key in an additional pKey parameter.
• Calls to dup(boolean) will return a SecondaryCursor.
• The dupSecondary(boolean) method is provided to return a SecondaryCursor that doesn't require casting.

To obtain a secondary cursor with default attributes:

    SecondaryCursor cursor = myDb.openSecondaryCursor(txn, null);

To customize the attributes of a cursor, use a CursorConfig object.

    CursorConfig config = new CursorConfig();
    config.setDirtyRead(true);
    SecondaryCursor cursor = myDb.openSecondaryCursor(txn, config);

Method Summary

Cursor	dup(boolean samePosition) Returns a new SecondaryCursor for the same transaction as the original cursor.
SecondaryCursor	dupSecondary(boolean samePosition) Returns a new copy of the cursor as a SecondaryCursor.
OperationStatus	getCurrent(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Returns the key/data pair to which the cursor refers.
OperationStatus	getFirst(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the first key/data pair of the database, and return that pair.
OperationStatus	getLast(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the last key/data pair of the database, and return that pair.
OperationStatus	getNext(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the next key/data pair and return that pair.
OperationStatus	getNextDup(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) If the next key/data pair of the database is a duplicate data record for the current key/data pair, move the cursor to the next key/data pair of the database and return that pair.
OperationStatus	getNextNoDup(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the next non-duplicate key/data pair and return that pair.
OperationStatus	getPrev(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the previous key/data pair and return that pair.
OperationStatus	getPrevDup(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) If the previous key/data pair of the database is a duplicate data record for the current key/data pair, move the cursor to the previous key/data pair of the database and return that pair.
OperationStatus	getPrevNoDup(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the previous non-duplicate key/data pair and return that pair.
OperationStatus	getRecordNumber(DatabaseEntry secondaryRecno, DatabaseEntry primaryRecno, LockMode lockMode) Return the record number associated with the cursor.
OperationStatus	getSearchBoth(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the specified secondary and primary key, where both the primary and secondary key items must match.
OperationStatus	getSearchBothRange(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the specified secondary key and closest matching primary key of the database.
OperationStatus	getSearchKey(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the given key of the database, and return the datum associated with the given key.
OperationStatus	getSearchKeyRange(DatabaseEntry key, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the closest matching key of the database, and return the data item associated with the matching key.
OperationStatus	getSearchRecordNumber(DatabaseEntry secondaryRecno, DatabaseEntry pKey, DatabaseEntry data, LockMode lockMode) Move the cursor to the specific numbered record of the database, and return the associated key/data pair.
SecondaryDatabase	getSecondaryDatabase() Return the SecondaryDatabase handle associated with this Cursor.

Methods inherited from class com.sleepycat.db.Cursor

close, count, delete, getConfig, getCurrent, getDatabase, getFirst, getLast, getNext, getNextDup, getNextNoDup, getPrev, getPrevDup, getPrevNoDup, getRecordNumber, getSearchBoth, getSearchBothRange, getSearchKey, getSearchKeyRange, getSearchRecordNumber, put, putAfter, putBefore, putCurrent, putKeyFirst, putKeyLast, putNoDupData, putNoOverwrite

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

dup

public Cursor dup(boolean samePosition)
           throws DatabaseException

Returns a new SecondaryCursor for the same transaction as the original cursor.

Overrides:

dup in class Cursor

Parameters:

samePosition - If true, the newly created cursor is initialized to refer to the same position in the database as the original cursor (if any) and hold the same locks (if any). If false, or the original cursor does not hold a database position and locks, the returned cursor is uninitialized and will behave like a newly created cursor.

Returns:

A new cursor with the same transaction and locker ID as the original cursor.

Throws:

DatabaseException - if a failure occurs.

dupSecondary

public SecondaryCursor dupSecondary(boolean samePosition)
                             throws DatabaseException

Returns a new copy of the cursor as a SecondaryCursor.

Calling this method is the equivalent of calling dup(boolean) and casting the result to SecondaryCursor.

Throws:

DatabaseException

See Also:

dup(boolean)

getCurrent

public OperationStatus getCurrent(DatabaseEntry key,
                                  DatabaseEntry pKey,
                                  DatabaseEntry data,
                                  LockMode lockMode)
                           throws DatabaseException

Returns the key/data pair to which the cursor refers.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.KEYEMPTY if the key/pair at the cursor position has been deleted; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getFirst

public OperationStatus getFirst(DatabaseEntry key,
                                DatabaseEntry pKey,
                                DatabaseEntry data,
                                LockMode lockMode)
                         throws DatabaseException

Move the cursor to the first key/data pair of the database, and return that pair. If the first key has duplicate values, the first data item in the set of duplicates is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getLast

public OperationStatus getLast(DatabaseEntry key,
                               DatabaseEntry pKey,
                               DatabaseEntry data,
                               LockMode lockMode)
                        throws DatabaseException

Move the cursor to the last key/data pair of the database, and return that pair. If the last key has duplicate values, the last data item in the set of duplicates is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getNext

public OperationStatus getNext(DatabaseEntry key,
                               DatabaseEntry pKey,
                               DatabaseEntry data,
                               LockMode lockMode)
                        throws DatabaseException

Move the cursor to the next key/data pair and return that pair. If the matching key has duplicate values, the first data item in the set of duplicates is returned.

If the cursor is not yet initialized, move the cursor to the first key/data pair of the database, and return that pair. Otherwise, the cursor is moved to the next key/data pair of the database, and that pair is returned. In the presence of duplicate key values, the value of the key may not change.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getNextDup

public OperationStatus getNextDup(DatabaseEntry key,
                                  DatabaseEntry pKey,
                                  DatabaseEntry data,
                                  LockMode lockMode)
                           throws DatabaseException

If the next key/data pair of the database is a duplicate data record for the current key/data pair, move the cursor to the next key/data pair of the database and return that pair.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getNextNoDup

public OperationStatus getNextNoDup(DatabaseEntry key,
                                    DatabaseEntry pKey,
                                    DatabaseEntry data,
                                    LockMode lockMode)
                             throws DatabaseException

Move the cursor to the next non-duplicate key/data pair and return that pair. If the matching key has duplicate values, the first data item in the set of duplicates is returned.

If the cursor is not yet initialized, move the cursor to the first key/data pair of the database, and return that pair. Otherwise, the cursor is moved to the next non-duplicate key of the database, and that key/data pair is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getPrev

public OperationStatus getPrev(DatabaseEntry key,
                               DatabaseEntry pKey,
                               DatabaseEntry data,
                               LockMode lockMode)
                        throws DatabaseException

Move the cursor to the previous key/data pair and return that pair. If the matching key has duplicate values, the last data item in the set of duplicates is returned.

If the cursor is not yet initialized, move the cursor to the last key/data pair of the database, and return that pair. Otherwise, the cursor is moved to the previous key/data pair of the database, and that pair is returned. In the presence of duplicate key values, the value of the key may not change.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getPrevDup

public OperationStatus getPrevDup(DatabaseEntry key,
                                  DatabaseEntry pKey,
                                  DatabaseEntry data,
                                  LockMode lockMode)
                           throws DatabaseException

If the previous key/data pair of the database is a duplicate data record for the current key/data pair, move the cursor to the previous key/data pair of the database and return that pair.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getPrevNoDup

public OperationStatus getPrevNoDup(DatabaseEntry key,
                                    DatabaseEntry pKey,
                                    DatabaseEntry data,
                                    LockMode lockMode)
                             throws DatabaseException

Move the cursor to the previous non-duplicate key/data pair and return that pair. If the matching key has duplicate values, the last data item in the set of duplicates is returned.

If the cursor is not yet initialized, move the cursor to the last key/data pair of the database, and return that pair. Otherwise, the cursor is moved to the previous non-duplicate key of the database, and that key/data pair is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key returned as output. Its byte array does not need to be initialized by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSearchKey

public OperationStatus getSearchKey(DatabaseEntry key,
                                    DatabaseEntry pKey,
                                    DatabaseEntry data,
                                    LockMode lockMode)
                             throws DatabaseException

Move the cursor to the given key of the database, and return the datum associated with the given key. If the matching key has duplicate values, the first data item in the set of duplicates is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key used as input. It must be initialized with a non-null byte array by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSearchKeyRange

public OperationStatus getSearchKeyRange(DatabaseEntry key,
                                         DatabaseEntry pKey,
                                         DatabaseEntry data,
                                         LockMode lockMode)
                                  throws DatabaseException

Move the cursor to the closest matching key of the database, and return the data item associated with the matching key. If the matching key has duplicate values, the first data item in the set of duplicates is returned.

The returned key/data pair is for the smallest key greater than or equal to the specified key (as determined by the key comparison function), permitting partial key matches and range searches.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key used as input and returned as output. It must be initialized with a non-null byte array by the caller.

pKey - the primary key returned as output. Its byte array does not need to be initialized by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSearchBoth

public OperationStatus getSearchBoth(DatabaseEntry key,
                                     DatabaseEntry pKey,
                                     DatabaseEntry data,
                                     LockMode lockMode)
                              throws DatabaseException

Move the cursor to the specified secondary and primary key, where both the primary and secondary key items must match.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key used as input. It must be initialized with a non-null byte array by the caller.

pKey - the primary key used as input. It must be initialized with a non-null byte array by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSearchBothRange

public OperationStatus getSearchBothRange(DatabaseEntry key,
                                          DatabaseEntry pKey,
                                          DatabaseEntry data,
                                          LockMode lockMode)
                                   throws DatabaseException

Move the cursor to the specified secondary key and closest matching primary key of the database.

In the case of any database supporting sorted duplicate sets, the returned key/data pair is for the smallest primary key greater than or equal to the specified primary key (as determined by the key comparison function), permitting partial matches and range searches in duplicate data sets.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

key - the secondary key used as input and returned as output. It must be initialized with a non-null byte array by the caller.

pKey - the primary key used as input and returned as output. It must be initialized with a non-null byte array by the caller.

data - the primary data returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSecondaryDatabase

public SecondaryDatabase getSecondaryDatabase()

Return the SecondaryDatabase handle associated with this Cursor.

Returns:

The SecondaryDatabase handle associated with this Cursor.

getRecordNumber

public OperationStatus getRecordNumber(DatabaseEntry secondaryRecno,
                                       DatabaseEntry primaryRecno,
                                       LockMode lockMode)
                                throws DatabaseException

Return the record number associated with the cursor. The record number will be returned in the data parameter.

For this method to be called, the underlying database must be of type Btree, and it must have been configured to support record numbers.

When called on a cursor opened on a database that has been made into a secondary index, the method returns the record numbers of both the secondary and primary databases. If either underlying database is not of type Btree or is not configured with record numbers, the out-of-band record number of 0 is returned.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

secondaryRecno - the secondary record number returned as output. Its byte array does not need to be initialized by the caller.

primaryRecno - the primary record number returned as output. Its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.

getSearchRecordNumber

public OperationStatus getSearchRecordNumber(DatabaseEntry secondaryRecno,
                                             DatabaseEntry pKey,
                                             DatabaseEntry data,
                                             LockMode lockMode)
                                      throws DatabaseException

Move the cursor to the specific numbered record of the database, and return the associated key/data pair.

The data field of the specified key must be a byte array containing a record number, as described in DatabaseEntry. This determines the record to be retrieved.

For this method to be called, the underlying database must be of type Btree, and it must have been configured to support record numbers.

If this method fails for any reason, the position of the cursor will be unchanged.

Parameters:

secondaryRecno - the secondary record number used as input. It must be initialized with a non-null byte array by the caller.

data - the primary data returned as output. Multiple results can be retrieved by passing an object that is a subclass of MultipleEntry, otherwise its byte array does not need to be initialized by the caller.

lockMode - the locking attributes; if null, default attributes are used.

Returns:

OperationStatus.NOTFOUND if no matching key/data pair is found; otherwise, OperationStatus.SUCCESS.

Throws:

NullPointerException - if a DatabaseEntry parameter is null or does not contain a required non-null byte array.

DeadlockException - if the operation was selected to resolve a deadlock.

IllegalArgumentException - if an invalid parameter was specified.

DatabaseException - if a failure occurs.