Module org.eclipse.persistence.core
Package org.eclipse.persistence.sequencing

Class DefaultSequence

java.lang.Object
org.eclipse.persistence.sequencing.Sequence
org.eclipse.persistence.sequencing.DefaultSequence
All Implemented Interfaces:
Serializable, Cloneable
public class DefaultSequence extends Sequence

Purpose: Reference to the default sequence.

Description This sequence can be used to provide a sequence using the session's default sequencing mechanism but override the pre-allocation size.

See Also:

  • Constructor Details

    • DefaultSequence

      public DefaultSequence()

    • DefaultSequence

      public DefaultSequence(String name)
      Create a new sequence with the name.

    • DefaultSequence

      public DefaultSequence(String name, int size)
      Create a new sequence with the name and sequence pre-allocation size.

    • DefaultSequence

      public DefaultSequence(String name, int size, int initialValue)

  • Method Details

    • getDefaultSequence

      public Sequence getDefaultSequence()
      INTERNAL: Return the platform's default sequence.

    • hasPreallocationSize

      public boolean hasPreallocationSize()

    • getPreallocationSize

      public int getPreallocationSize()
      Overrides:
      getPreallocationSize in class Sequence

    • getInitialValue

      public int getInitialValue()
      Overrides:
      getInitialValue in class Sequence

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Sequence

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Sequence

    • shouldAcquireValueAfterInsert

      public boolean shouldAcquireValueAfterInsert()
      INTERNAL: Indicates whether sequencing value should be acquired after INSERT. Note that preallocation could be used only in case sequencing values should be acquired before insert (this method returns false). In default implementation, it is true for table sequencing and native sequencing on Oracle platform, false for native sequencing on other platforms.
      Specified by:
      shouldAcquireValueAfterInsert in class Sequence

    • shouldAlwaysOverrideExistingValue

      public boolean shouldAlwaysOverrideExistingValue(String seqName)
      INTERNAL: Indicates whether the existing pk value should always be overridden by the sequence.
      Overrides:
      shouldAlwaysOverrideExistingValue in class Sequence

    • shouldUsePreallocation

      public boolean shouldUsePreallocation()
      INTERNAL: Indicates whether several sequencing values should be acquired at a time and be kept by TopLink. This in only possible in case sequencing numbers should be acquired before insert (shouldAcquireValueAfterInsert()==false). In default implementation, it is true for table sequencing and native sequencing on Oracle platform, false for native sequencing on other platforms.
      Overrides:
      shouldUsePreallocation in class Sequence

    • shouldUseTransaction

      public boolean shouldUseTransaction()
      INTERNAL: Indicates whether EclipseLink should internally call beginTransaction() before getGeneratedValue/Vector, and commitTransaction after. In default implementation, it is true for table sequencing and false for native sequencing.
      Specified by:
      shouldUseTransaction in class Sequence

    • getGeneratedValue

      public Object getGeneratedValue(Accessor accessor, AbstractSession writeSession, String seqName)
      INTERNAL: Return the newly-generated sequencing value. Used only in case preallocation is not used (shouldUsePreallocation()==false). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
      Specified by:
      getGeneratedValue in class Sequence
      Parameters:
      accessor - Accessor is a separate sequencing accessor (may be null);
      writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
      seqName - String is sequencing number field name

    • getGeneratedVector

      public Vector<?> getGeneratedVector(Accessor accessor, AbstractSession writeSession, String seqName, int size)
      INTERNAL: Return a Vector of newly-generated sequencing values. Used only in case preallocation is used (shouldUsePreallocation()==true). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
      Specified by:
      getGeneratedVector in class Sequence
      Parameters:
      accessor - Accessor is a separate sequencing accessor (may be null);
      writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
      seqName - String is sequencing number field name
      size - int number of values to preallocate (output Vector size).

    • onConnect

      public void onConnect()
      INTERNAL: This method is called when Sequencing object is created. It's a chance to do initialization.
      Specified by:
      onConnect in class Sequence

    • onDisconnect

      public void onDisconnect()
      INTERNAL: This method is called when Sequencing object is destroyed.. It's a chance to do deinitialization.
      Specified by:
      onDisconnect in class Sequence

    • isConnected

      public boolean isConnected()
      PUBLIC: Indicates that Sequence is connected.
      Overrides:
      isConnected in class Sequence

    • setQualifier

      public void setQualifier(String qualifier)
      INTERNAL: Ignored, getDefaultSequence().getQualifier() used instead.
      Overrides:
      setQualifier in class Sequence