org.datanucleus.store.valuegenerator
Interface ValueGenerator

All Known Implementing Classes:
AbstractDatastoreGenerator, AbstractGenerator, AbstractUIDGenerator, AbstractUUIDGenerator, AUIDGenerator, TimestampGenerator, TimestampValueGenerator, UUIDHexGenerator, UUIDStringGenerator

public interface ValueGenerator

Generator interface for values. Uses the same methods as in the javax.jdo.datastore.Sequence interface


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

Method Detail

getName

java.lang.String getName()
Returns the fully qualified name of the Sequence.

Returns:
the name of the sequence

next

java.lang.Object next()
Returns the next sequence value as an Object. If the next sequence value is not available, throw NucleusDataStoreException.

Returns:
the next value

allocate

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

java.lang.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 NucleusDataStoreException.

Returns:
the current value

nextValue

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

Returns:
the next value

currentValue

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

Returns:
the current value


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