Package org.hibernate.id.enhanced

Class PooledLoOptimizer

java.lang.Object
org.hibernate.id.enhanced.AbstractOptimizer
org.hibernate.id.enhanced.PooledLoOptimizer
All Implemented Interfaces:
Optimizer
public class PooledLoOptimizer extends AbstractOptimizer
Optimizer which uses a pool of values, backed by a logical sequence. A logical sequence is usually just an unpooled sequence or table generator.

The pool size is controlled by the allocationSize of a sequence generator or sequence generator.

From time to time, the optimizer allocates a range of values to itself, interpreting the next value retrieved from the logical sequence as the lower bound on the range of newly allocated ids. Thus, the generated ids begin with the value retrieved from the logical sequence.

The PooledOptimizer is similar, but interprets the current value of the logical sequence as an upper bound on the range of already-allocated ids.

See Also:

  • Constructor Details

    • PooledLoOptimizer

      public PooledLoOptimizer(Class<?> returnClass, int incrementSize)
      Constructs a PooledLoOptimizer.
      Parameters:
      returnClass - The Java type of the values to be generated
      incrementSize - The increment size.

  • Method Details

    • generate

      public Serializable generate(AccessCallback callback)
      Description copied from interface: Optimizer
      Generate an identifier value accounting for this specific optimization.
      Parameters:
      callback - Callback to access the underlying value source.
      Returns:
      The generated identifier value.

    • reset

      public void reset()
      Description copied from interface: Optimizer
      Reset the optimizer before restarting the underlying database sequence.

    • getLastSourceValue

      public IntegralDataTypeHolder getLastSourceValue()
      Description copied from interface: Optimizer
      A common means to access the last value obtained from the underlying source. This is intended for testing purposes, since accessing the underlying database source directly is much more difficult.
      Returns:
      The last value we obtained from the underlying source; null indicates we have not yet consulted with the source.

    • applyIncrementSizeToSourceValues

      public boolean applyIncrementSizeToSourceValues()
      Description copied from interface: Optimizer
      Are increments to be applied to the values stored in the underlying value source?
      Returns:
      True if the values in the source are to be incremented according to the defined increment size; false otherwise, in which case the increment size is a completely in-memory construct.

    • createLowValueExpression

      public Expression createLowValueExpression(Expression databaseValue, SessionFactoryImplementor sessionFactory)
      Description copied from interface: Optimizer
      Creates an expression representing the low/base value for ID allocation in batch insert operations.

      Each optimizer implementation should define its own strategy for calculating the starting value of a sequence range.

      Parameters:
      databaseValue - The expression representing the next value from database sequence
      sessionFactory - The session factory
      Returns:
      An expression that calculates the low/base value according to the optimizer strategy