com.sleepycat.persist
Interface ForwardCursor<V>

All Superinterfaces:

Closeable, Iterable<V>

All Known Subinterfaces:

EntityCursor<V>

public interface ForwardCursor<V>
extends Iterable<V>, Closeable

Cursor operations limited to traversing forward. See EntityCursor for general information on cursors.

ForwardCursor objects are not thread-safe. Cursors should be opened, used and closed by a single thread.

WARNING: Cursors must always be closed to prevent resource leaks which could lead to the index becoming unusable or cause an OutOfMemoryError. To ensure that a cursor is closed in the face of exceptions, close it in a finally block.

Author:

Mark Hayes

Method Summary

void	close() Closes the cursor.
Iterator<V>	iterator() Returns an iterator over the key range, starting with the value following the current position or at the first value if the cursor is uninitialized.
Iterator<V>	iterator(LockMode lockMode) Returns an iterator over the key range, starting with the value following the current position or at the first value if the cursor is uninitialized.
V	next() Moves the cursor to the next value and returns it, or returns null if there are no more values in the cursor range.
V	next(LockMode lockMode) Moves the cursor to the next value and returns it, or returns null if there are no more values in the cursor range.

Method Detail

next

V next()
       throws DatabaseException

Moves the cursor to the next value and returns it, or returns null if there are no more values in the cursor range. If the cursor is uninitialized, this method returns the first value.

LockMode.DEFAULT is used implicitly.

Returns:

the next value, or null if there are no more values in the cursor range.

Throws:

OperationFailureException - if one of the Read Operation Failures occurs.

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs.

DatabaseException - the base class for all BDB exceptions.

next

V next(LockMode lockMode)
       throws DatabaseException

Moves the cursor to the next value and returns it, or returns null if there are no more values in the cursor range. If the cursor is uninitialized, this method returns the first value.

Parameters:

lockMode - the lock mode to use for this operation, or null to use LockMode.DEFAULT.

Returns:

the next value, or null if there are no more values in the cursor range.

Throws:

OperationFailureException - if one of the Read Operation Failures occurs.

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs.

DatabaseException - the base class for all BDB exceptions.

iterator

Iterator<V> iterator()

Returns an iterator over the key range, starting with the value following the current position or at the first value if the cursor is uninitialized.

LockMode.DEFAULT is used implicitly.

Specified by:

iterator in interface Iterable<V>

Returns:

the iterator.

iterator

Iterator<V> iterator(LockMode lockMode)

Returns an iterator over the key range, starting with the value following the current position or at the first value if the cursor is uninitialized.

Parameters:

lockMode - the lock mode to use for all operations performed using the iterator, or null to use LockMode.DEFAULT.

Returns:

the iterator.

close

void close()
           throws DatabaseException

Closes the cursor.

Specified by:

close in interface Closeable

Throws:

DatabaseException - the base class for all BDB exceptions.