Cursor (Oracle - Berkeley DB Java API)
Keywords: com.sleepycat.db.Cursor class

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## com.sleepycat.db
Class Cursor

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

Direct Known Subclasses:
  SecondaryCursor

    public class Cursor

extends Object

A database cursor. Cursors are used for operating on collections of records, for iterating over a database, and for saving handles to individual records, so that they can be modified after they have been read.

Cursors may be used by multiple threads, but only serially. That is, the application must serialize access to the handle.

If the cursor is to be used to perform operations on behalf of a transaction, the cursor must be opened and closed within the context of that single transaction.

Once the cursor close method has been called, the handle may not be accessed again, regardless of the close method's success or failure.

To obtain a cursor with default attributes:

>         Cursor cursor = myDatabase.openCursor(txn, null);

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

>         CursorConfig config = new CursorConfig();
>         config.setDirtyRead(true);
>         Cursor cursor = myDatabase.openCursor(txn, config);

Modifications to the database during a sequential scan will be reflected in the scan; that is, records inserted behind a cursor will not be returned while records inserted in front of a cursor will be returned. In Queue and Recno databases, missing entries (that is, entries that were never explicitly created or that were created and then deleted) will be ignored during a sequential scan.

Method Summary
`void` | `close()` Discard the cursor.
`int` | `count()` Return a count of the number of data items for the key to which the cursor refers.
`OperationStatus` | `delete()` Delete the key/data pair to which the cursor refers.
`Cursor` | `dup(boolean samePosition)` Return a new cursor with the same transaction and locker ID as the original cursor.
`CursorConfig` | `getConfig()` Return this cursor's configuration.
`OperationStatus` | `getCurrent(DatabaseEntry key, DatabaseEntry data, LockMode lockMode)` Returns the key/data pair to which the cursor refers.
`Database` | `getDatabase()` Return the Database handle associated with this Cursor.
`OperationStatus` | `getFirst(DatabaseEntry key, 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 data, LockMode lockMode)` Move the cursor to the last key/data pair of the database, and return that pair.
`OperationStatus` | `getNext(DatabaseEntry key, DatabaseEntry data, LockMode lockMode)` Move the cursor to the next key/data pair and return that pair.
`OperationStatus` | `getNextDup(DatabaseEntry key, 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 data, LockMode lockMode)` Move the cursor to the next non-duplicate key/data pair and return that pair.
`OperationStatus` | `getPrev(DatabaseEntry key, DatabaseEntry data, LockMode lockMode)` Move the cursor to the previous key/data pair and return that pair.
`OperationStatus` | `getPrevDup(DatabaseEntry key, 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 data, LockMode lockMode)` Move the cursor to the previous non-duplicate key/data pair and return that pair.
`CacheFilePriority` | `getPriority()` Get the cache priority for pages referenced by the cursor.
`OperationStatus` | `getRecordNumber(DatabaseEntry data, LockMode lockMode)` Return the record number associated with the cursor.
`OperationStatus` | `getSearchBoth(DatabaseEntry key, DatabaseEntry data, LockMode lockMode)` Move the cursor to the specified key/data pair, where both the key and data items must match.
`OperationStatus` | `getSearchBothRange(DatabaseEntry key, DatabaseEntry data, LockMode lockMode)` Move the cursor to the specified key and closest matching data item of the database.
`OperationStatus` | `getSearchKey(DatabaseEntry key, 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 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 key, DatabaseEntry data, LockMode lockMode)` Move the cursor to the specific numbered record of the database, and return the associated key/data pair.
`OperationStatus` | `put(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putAfter(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putBefore(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putCurrent(DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putKeyFirst(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putKeyLast(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putNoDupData(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`OperationStatus` | `putNoOverwrite(DatabaseEntry key, DatabaseEntry data)` Store a key/data pair into the database.
`void` | `setPriority(CacheFilePriority priority)` Set the cache priority for pages referenced by the DBC handle.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Method Detail

### getDatabase

    public Database getDatabase()

  Return the Database handle associated with this Cursor.

  Returns:
    The Database handle associated with this Cursor.

### getConfig

    public CursorConfig getConfig()

  Return this cursor's configuration.

  This may differ from the configuration used to open this object if the cursor existed previously.

  Returns:
    This cursor's configuration.

  Throws:
    `DatabaseException` - if a failure occurs.

### close

    public void close()
               throws DatabaseException

  Discard the cursor.

  This method may throw a DeadlockException, signaling the enclosing transaction should be aborted. If the application is already intending to abort the transaction, this error can be ignored, and the application should proceed.

  The cursor handle may not be used again after this method has been called, regardless of the method's success or failure.

  Throws:
    `DatabaseException` - if a failure occurs.

### count

    public int count()
              throws DatabaseException

  Return a count of the number of data items for the key to which the cursor refers.

  Returns:
    A count of the number of data items for the key to which the cursor refers.

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

    `DatabaseException` - if a failure occurs.

### dup

    public Cursor dup(boolean samePosition)
               throws DatabaseException

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

  This is useful when an application is using locking and requires two or more cursors in the same thread of control.

  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.

### delete

    public OperationStatus delete()
                           throws DatabaseException

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

  When called on a cursor opened on a database that has been made into a secondary index, this method the key/data pair from the primary database and all secondary indices.

  The cursor position is unchanged after a delete, and subsequent calls to cursor functions expecting the cursor to refer to an existing key will fail.

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

    `DatabaseException` - if a failure occurs.

### put

    public OperationStatus put(DatabaseEntry key,
                               DatabaseEntry data)
                        throws DatabaseException

  Store a key/data pair into the database.

  If the put method succeeds, the cursor is always positioned to refer to the newly inserted item. If the put method fails for any reason, the state of the cursor will be unchanged.

  If the key already appears in the database and duplicates are supported, the new data value is inserted at the correct sorted location. If the key already appears in the database and duplicates are not supported, the existing key/data pair will be replaced.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putNoOverwrite

    public OperationStatus putNoOverwrite(DatabaseEntry key,
                                          DatabaseEntry data)
                                   throws DatabaseException

  Store a key/data pair into the database.

  If the putNoOverwrite method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putNoOverwrite method fails for any reason, the state of the cursor will be unchanged.

  If the key already appears in the database, putNoOverwrite will return `OperationStatus.KEYEXIST`.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putNoDupData

    public OperationStatus putNoDupData(DatabaseEntry key,
                                        DatabaseEntry data)
                                 throws DatabaseException

  Store a key/data pair into the database.

  If the putNoDupData method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putNoDupData method fails for any reason, the state of the cursor will be unchanged.

  In the case of the Btree and Hash access methods, insert the specified key/data pair into the database, unless a key/data pair comparing equally to it already exists in the database. If a matching key/data pair already exists in the database, `OperationStatus.KEYEXIST` is returned.

  This method may only be called if the underlying database has been configured to support sorted duplicate data items.

  This method may not be called for the Queue or Recno access methods.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putCurrent

    public OperationStatus putCurrent(DatabaseEntry data)
                               throws DatabaseException

  Store a key/data pair into the database.

  If the putCurrent method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putCurrent method fails for any reason, the state of the cursor will be unchanged.

  Overwrite the data of the key/data pair to which the cursor refers with the specified data item. This method will return `OperationStatus.NOTFOUND` if the cursor currently refers to an already-deleted key/data pair.

  Parameters:
    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putAfter

    public OperationStatus putAfter(DatabaseEntry key,
                                    DatabaseEntry data)
                             throws DatabaseException

  Store a key/data pair into the database.

  If the putAfter method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putAfter method fails for any reason, the state of the cursor will be unchanged.

  In the case of the Btree and Hash access methods, insert the data element as a duplicate element of the key to which the cursor refers. The new element appears immediately after the current cursor position. It is an error to call this method if the underlying Btree or Hash database does not support duplicate data items. The key parameter is ignored.

  In the case of the Hash access method, the putAfter method will fail and throw an exception if the current cursor record has already been deleted.

  In the case of the Recno access method, it is an error to call this method if the underlying Recno database was not configured to have mutable record numbers. A new key is created, all records after the inserted item are automatically renumbered, and the key of the new record is returned in the key parameter. The initial value of the key parameter is ignored.

  The putAfter method may not be called for the Queue access method.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putBefore

    public OperationStatus putBefore(DatabaseEntry key,
                                     DatabaseEntry data)
                              throws DatabaseException

  Store a key/data pair into the database.

  If the putBefore method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putBefore method fails for any reason, the state of the cursor will be unchanged.

  In the case of the Btree and Hash access methods, insert the data element as a duplicate element of the key to which the cursor refers. The new element appears immediately before the current cursor position. It is an error to call this method if the underlying Btree or Hash database does not support duplicate data items. The key parameter is ignored.

  In the case of the Hash access method, the putBefore method will fail and throw an exception if the current cursor record has already been deleted.

  In the case of the Recno access method, it is an error to call this method if the underlying Recno database was not configured to have mutable record numbers. A new key is created, all records after the inserted item are automatically renumbered, and the key of the new record is returned in the key parameter. The initial value of the key parameter is ignored.

  The putBefore method may not be called for the Queue access method.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putKeyFirst

    public OperationStatus putKeyFirst(DatabaseEntry key,
                                       DatabaseEntry data)
                                throws DatabaseException

  Store a key/data pair into the database.

  If the putKeyFirst method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putKeyFirst method fails for any reason, the state of the cursor will be unchanged.

  In the case of the Btree and Hash access methods, insert the specified key/data pair into the database.

  If the underlying database supports duplicate data items, and if the key already exists in the database and a duplicate sort function has been specified, the inserted data item is added in its sorted location. If the key already exists in the database and no duplicate sort function has been specified, the inserted data item is added as the first of the data items for that key.

  The putKeyFirst method may not be called for the Queue or Recno access methods.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### putKeyLast

    public OperationStatus putKeyLast(DatabaseEntry key,
                                      DatabaseEntry data)
                               throws DatabaseException

  Store a key/data pair into the database.

  If the putKeyLast method succeeds, the cursor is always positioned to refer to the newly inserted item. If the putKeyLast method fails for any reason, the state of the cursor will be unchanged.

  In the case of the Btree and Hash access methods, insert the specified key/data pair into the database.

  If the underlying database supports duplicate data items, and if the key already exists in the database and a duplicate sort function has been specified, the inserted data item is added in its sorted location. If the key already exists in the database and no duplicate sort function has been specified, the inserted data item is added as the last of the data items for that key.

  The putKeyLast method may not be called for the Queue or Recno access methods.

  Parameters:
    `key` - the key `DatabaseEntry` operated on.

    `data` - the data `DatabaseEntry` stored.

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

    `IllegalArgumentException` - if an invalid parameter was specified.

    `DatabaseException` - if a failure occurs.

### getCurrent

    public OperationStatus getCurrent(DatabaseEntry key,
                                      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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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 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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getLast

    public OperationStatus getLast(DatabaseEntry key,
                                   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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getNext

    public OperationStatus getNext(DatabaseEntry key,
                                   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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getNextDup

    public OperationStatus getNextDup(DatabaseEntry key,
                                      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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getNextNoDup

    public OperationStatus getNextNoDup(DatabaseEntry key,
                                        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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getPrev

    public OperationStatus getPrev(DatabaseEntry key,
                                   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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getPrevDup

    public OperationStatus getPrevDup(DatabaseEntry key,
                                      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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getPrevNoDup

    public OperationStatus getPrevNoDup(DatabaseEntry key,
                                        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 key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getSearchKey

    public OperationStatus getSearchKey(DatabaseEntry key,
                                        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 key used as input. It must be initialized with a non-null byte array by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getSearchKeyRange

    public OperationStatus getSearchKeyRange(DatabaseEntry key,
                                             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 key used as input and returned as output. It must be initialized with a non-null byte array by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getSearchBoth

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

  Move the cursor to the specified key/data pair, where both the key and data items must match.

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

  Parameters:
    `key` - the key used as input. It must be initialized with a non-null byte array by the caller.
    `data` - the data used as input. It must be initialized with a non-null byte array by the caller.
    `lockMode` - the locking attributes; if null, default attributes are used.
  Returns:
    `OperationStatus.NOTFOUND` if no matching key/data pair is found; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getSearchBothRange

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

  Move the cursor to the specified key and closest matching data item of the database.

  In the case of any database supporting sorted duplicate sets, the returned key/data pair is for the smallest data item greater than or equal to the specified data item (as determined by the duplicate 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 key used as input and returned as output. It must be initialized with a non-null byte array by the caller.
    `data` - the data used as input and returned as output. It must be initialized with a non-null byte array by the caller.
    `lockMode` - the locking attributes; if null, default attributes are used.
  Returns:
    `OperationStatus.NOTFOUND` if no matching key/data pair is found; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getRecordNumber

    public OperationStatus getRecordNumber(DatabaseEntry data,
                                           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.

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

  Parameters:
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getSearchRecordNumber

    public OperationStatus getSearchRecordNumber(DatabaseEntry key,
                                                 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:
    `key` - the key returned as output. Its byte array does not need to be initialized by the caller.
    `data` - the 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; `OperationStatus.KEYEMPTY` if the database is a Queue or Recno database and the specified key exists, but was never explicitly created by the application or was later 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.

### getPriority

    public CacheFilePriority getPriority()
                                  throws DatabaseException

  Get the cache priority for pages referenced by the cursor.

  This method may be called at any time during the life of the application.

  Throws:
    `DatabaseException` - if a failure occurs.

### setPriority

    public void setPriority(CacheFilePriority priority)
                     throws DatabaseException

  Set the cache priority for pages referenced by the DBC handle.

  The priority of a page biases the replacement algorithm to be more or less likely to discard a page when space is needed in the buffer pool. The bias is temporary, and pages will eventually be discarded if they are not referenced again. The DBcursor->set_priority method is only advisory, and does not guarantee pages will be treated in a specific way.

  This method may be called at any time during the life of the application.

  Throws:
    `DatabaseException` - if a failure occurs.

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