javax.jdo.datastore

Interface Sequence

public interface Sequence

Implementations of this interface can be used to obtain sequences. The behavior with regard to the transaction and rollover behavior are defined in the metadata.
Version:
2.0
Since:
2.0

Method Summary

void
allocate(int additional)
Provides a hint to the implementation that the application will need additional sequence value objects in short order.
Object
current()
Returns the current sequence value object if it is available.
long
currentValue()
Returns the current sequence value as a long.
String
getName()
Returns the fully qualified name of the Sequence.
Object
next()
Returns the next sequence value as an Object.
long
nextValue()
Returns the next sequence value as a long.

Method Details

allocate

public void allocate(int additional)
Provides a hint to the implementation that the application will need additional sequence value objects in short order. There is no externally visible behavior of this method. It is used to potentially improve the efficiency of the algorithm of obtaining additional sequence value objects.
Parameters:
additional - the number of additional values to allocate

current

public Object current()
Returns the current sequence value object if it is available. It is intended to return a sequence value object previously used. If the current sequence value is not available, throw JDODataStoreException.
Returns:
the current value

currentValue

public long currentValue()
Returns the current sequence value as a long. If the current sequence value is not available or is not numeric, throw JDODataStoreException.
Returns:
the current value

getName

public String getName()
Returns the fully qualified name of the Sequence.
Returns:
the name of the sequence

next

public Object next()
Returns the next sequence value as an Object. If the next sequence value is not available, throw JDODataStoreException.
Returns:
the next value

nextValue

public long nextValue()
Returns the next sequence value as a long. If the next sequence value is not available or is not numeric, throw JDODataStoreException.
Returns:
the next value