Package org.eclipse.persistence.mappings.structures

Class NestedTableMapping

java.lang.Object
org.eclipse.persistence.core.mappings.CoreMapping<AttributeAccessor,org.eclipse.persistence.internal.sessions.AbstractSession,org.eclipse.persistence.internal.queries.ContainerPolicy,ClassDescriptor,org.eclipse.persistence.internal.helper.DatabaseField>
org.eclipse.persistence.mappings.DatabaseMapping
org.eclipse.persistence.mappings.ForeignReferenceMapping
org.eclipse.persistence.mappings.CollectionMapping
org.eclipse.persistence.mappings.structures.NestedTableMapping
All Implemented Interfaces:
Serializable, Cloneable, ContainerMapping
public class NestedTableMapping extends CollectionMapping

Purpose: Nested tables are similar to VARRAYs except internally they store their information in a separate table from their parent structure's table. The advantage of nested tables is that they support querying and joining much better than varrays that are inlined into the parent table. A nested table is typically used to represent a one-to-many or many-to-many relationship of references to another independent structure. TopLink supports storing a nested table of values into a single field.

NOTE: Only Oracle8i supports nested tables type.

See Also:

  • Field Details

    • nestedMapping

      protected DatabaseMapping nestedMapping

    • field

      protected org.eclipse.persistence.internal.helper.DatabaseField field
      A ref is always stored in a single field.

    • structureName

      protected String structureName
      Arrays require a structure name, this is the ADT defined for the VARRAY.

  • Constructor Details

    • NestedTableMapping

      public NestedTableMapping()
      PUBLIC: Default constructor.

  • Method Details

    • buildExpression

      public Expression buildExpression(Object queryObject, QueryByExamplePolicy policy, Expression expressionBuilder, Map processedObjects, org.eclipse.persistence.internal.sessions.AbstractSession session)
      INTERNAL: In case Query By Example is used, this method builds and returns an expression that corresponds to a single attribute and it's value.
      Overrides:
      buildExpression in class CollectionMapping

    • clone

      public Object clone()
      INTERNAL: The mapping clones itself to create deep copy
      Overrides:
      clone in class CollectionMapping

    • collectFields

      protected Vector collectFields()
      Returns all the aggregate fields.
      Overrides:
      collectFields in class DatabaseMapping

    • getField

      public org.eclipse.persistence.internal.helper.DatabaseField getField()
      INTERNAL: Returns the field which this mapping represents.
      Overrides:
      getField in class DatabaseMapping

    • getFieldName

      public String getFieldName()
      PUBLIC: Return the name of the field this mapping represents.

    • getJoinCriteria

      public Expression getJoinCriteria(org.eclipse.persistence.internal.expressions.ObjectExpression context, Expression base)
      INTERNAL: Join criteria is created to read target records (nested table) from the table.
      Overrides:
      getJoinCriteria in class CollectionMapping

    • getStructureName

      public String getStructureName()
      PUBLIC: Return the structure name of the nestedTable. This is the name of the user defined data type as defined on the database.

    • hasConstraintDependency

      public boolean hasConstraintDependency()
      INTERNAL: The returns if the mapping has any constraint dependencies, such as foreign keys and join tables.
      Overrides:
      hasConstraintDependency in class DatabaseMapping

    • initialize

      public void initialize(org.eclipse.persistence.internal.sessions.AbstractSession session) throws DescriptorException
      INTERNAL: Initialize the mapping.
      Overrides:
      initialize in class CollectionMapping
      Throws:
      DescriptorException

    • initializeSelectionCriteria

      protected void initializeSelectionCriteria(org.eclipse.persistence.internal.sessions.AbstractSession session)
      INTERNAL: Selection criteria is created to read target records (nested table) from the table.

    • isNestedTableMapping

      public boolean isNestedTableMapping()
      INTERNAL:
      Overrides:
      isNestedTableMapping in class DatabaseMapping

    • postInitialize

      public void postInitialize(org.eclipse.persistence.internal.sessions.AbstractSession session) throws DescriptorException
      INTERNAL: Post Initialize the mapping.
      Overrides:
      postInitialize in class CollectionMapping
      Throws:
      DescriptorException

    • preDelete

      public void preDelete(DeleteObjectQuery query) throws DatabaseException, OptimisticLockException
      INTERNAL: Delete privately owned parts
      Overrides:
      preDelete in class DatabaseMapping
      Throws:
      DatabaseException
      OptimisticLockException

    • preInsert

      public void preInsert(WriteObjectQuery query) throws DatabaseException, OptimisticLockException
      INTERNAL: Insert privately owned parts
      Overrides:
      preInsert in class CollectionMapping
      Throws:
      DatabaseException
      OptimisticLockException

    • preUpdate

      public void preUpdate(WriteObjectQuery query) throws DatabaseException, OptimisticLockException
      INTERNAL: Update the privately owned parts
      Overrides:
      preUpdate in class CollectionMapping
      Throws:
      DatabaseException
      OptimisticLockException

    • setField

      protected void setField(org.eclipse.persistence.internal.helper.DatabaseField theField)
      Set the field in the mapping.

    • setFieldName

      public void setFieldName(String FieldName)
      PUBLIC: Set the field name in the mapping.

    • setStructureName

      public void setStructureName(String structureName)
      PUBLIC: Set the name of the structure. This is the name of the user defined nested table data type as defined on the database.

    • verifyDeleteForUpdate

      protected void verifyDeleteForUpdate(DeleteObjectQuery query) throws DatabaseException, OptimisticLockException
      INTERNAL: Verifying deletes make sure that all the records privately owned by this mapping are actually removed. If such records are found then those are all read and removed one by one taking their privately owned parts into account.
      Throws:
      DatabaseException
      OptimisticLockException

    • writeFromObjectIntoRow

      public void writeFromObjectIntoRow(Object object, org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session, DatabaseMapping.WriteType writeType)
      INTERNAL: Get a value from the object and set that in the respective field of the row.
      Overrides:
      writeFromObjectIntoRow in class DatabaseMapping

    • writeFromObjectIntoRowWithChangeRecord

      public void writeFromObjectIntoRowWithChangeRecord(org.eclipse.persistence.internal.sessions.ChangeRecord changeRecord, org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session, DatabaseMapping.WriteType writeType)
      INTERNAL: Get a value from the object and set that in the respective field of the row.
      Overrides:
      writeFromObjectIntoRowWithChangeRecord in class DatabaseMapping

    • writeFromObjectIntoRowForShallowInsert

      public void writeFromObjectIntoRowForShallowInsert(Object object, org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session)
      INTERNAL: This row is built for shallow insert which happens in case of bidirectional inserts. The foreign keys must be set to null to avoid constraints.
      Overrides:
      writeFromObjectIntoRowForShallowInsert in class DatabaseMapping

    • writeFromObjectIntoRowForUpdateAfterShallowInsert

      public void writeFromObjectIntoRowForUpdateAfterShallowInsert(Object object, org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session, org.eclipse.persistence.internal.helper.DatabaseTable table)
      INTERNAL: This row is built for update after shallow insert which happens in case of bidirectional inserts. It contains the foreign keys with non null values that were set to null for shallow insert.
      Overrides:
      writeFromObjectIntoRowForUpdateAfterShallowInsert in class DatabaseMapping

    • writeFromObjectIntoRowForShallowInsertWithChangeRecord

      public void writeFromObjectIntoRowForShallowInsertWithChangeRecord(org.eclipse.persistence.internal.sessions.ChangeRecord changeRecord, org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session)
      INTERNAL: This row is built for shallow insert which happens in case of bidirectional inserts. The foreign keys must be set to null to avoid constraints.
      Overrides:
      writeFromObjectIntoRowForShallowInsertWithChangeRecord in class DatabaseMapping

    • writeFromObjectIntoRowForUpdate

      public void writeFromObjectIntoRowForUpdate(WriteObjectQuery writeQuery, org.eclipse.persistence.internal.sessions.AbstractRecord record) throws DescriptorException
      INTERNAL: Write the entire structure into the row as a special type that prints as the constructor. If any part of the structure has changed the whole thing is written.
      Overrides:
      writeFromObjectIntoRowForUpdate in class DatabaseMapping
      Throws:
      DescriptorException

    • writeInsertFieldsIntoRow

      public void writeInsertFieldsIntoRow(org.eclipse.persistence.internal.sessions.AbstractRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session)
      INTERNAL: Write fields needed for insert into the template for with null values.
      Overrides:
      writeInsertFieldsIntoRow in class DatabaseMapping