/** INTERNAL: Get a value from the object and set that in the respective field of the row. */
  @Override
  public Object valueFromObject(Object object, DatabaseField field, AbstractSession session) {
    // First check if the value can be obtained from the value holder's row.
    AbstractRecord referenceRow =
        getIndirectionPolicy().extractReferenceRow(getAttributeValueFromObject(object));
    if (referenceRow != null) {
      Object value = referenceRow.get(field);

      // Must ensure the classification to get a cache hit.
      try {
        value = session.getDatasourcePlatform().convertObject(value, getFieldClassification(field));
      } catch (ConversionException e) {
        throw ConversionException.couldNotBeConverted(this, getDescriptor(), e);
      }

      return value;
    }

    // 2.5.1.6 PWK.  added to support batch reading on variable one to ones
    Object referenceObject = getRealAttributeValueFromObject(object, session);
    String queryKeyName = (String) getSourceToTargetQueryKeyNames().get(field);
    ClassDescriptor objectDescriptor = session.getDescriptor(referenceObject.getClass());
    DatabaseField targetField =
        objectDescriptor.getObjectBuilder().getTargetFieldForQueryKeyName(queryKeyName);

    if (targetField == null) {
      return null;
    }

    return objectDescriptor
        .getObjectBuilder()
        .extractValueFromObjectForField(referenceObject, targetField, session);
  }
  /**
   * INTERNAL: Return the value of the field from the row or a value holder on the query to obtain
   * the object. Check for batch + aggregation reading.
   */
  @Override
  public Object valueFromRow(
      AbstractRecord row,
      JoinedAttributeManager joinManager,
      ObjectBuildingQuery sourceQuery,
      AbstractSession executionSession)
      throws DatabaseException {
    // If any field in the foreign key is null then it means there are no referenced objects
    for (Enumeration enumeration = getFields().elements(); enumeration.hasMoreElements(); ) {
      DatabaseField field = (DatabaseField) enumeration.nextElement();
      if (row.get(field) == null) {
        return getIndirectionPolicy().nullValueFromRow();
      }
    }

    if (getTypeField() != null) {
      // If the query used batched reading, return a special value holder,
      // or retrieve the object from the query property.
      if (sourceQuery.isReadAllQuery()
          && (((ReadAllQuery) sourceQuery).isAttributeBatchRead(getDescriptor(), getAttributeName())
              || shouldUseBatchReading())) {
        return batchedValueFromRow(row, ((ReadAllQuery) sourceQuery));
      }

      // If the field is empty we cannot load the object because we do not know what class it will
      // be
      if (row.get(getTypeField()) == null) {
        return getIndirectionPolicy().nullValueFromRow();
      }
      Class implementerClass =
          (Class) getImplementorForType(row.get(getTypeField()), executionSession);
      ReadObjectQuery query = (ReadObjectQuery) getSelectionQuery().clone();
      query.setReferenceClass(implementerClass);
      query.setSelectionCriteria(getSelectionCriteria());
      query.setDescriptor(null); // Must set to null so the right descriptor is used

      if (sourceQuery.isObjectLevelReadQuery()
          && (sourceQuery.shouldCascadeAllParts()
              || (sourceQuery.shouldCascadePrivateParts() && isPrivateOwned())
              || (sourceQuery.shouldCascadeByMapping() && this.cascadeRefresh))) {
        query.setShouldRefreshIdentityMapResult(sourceQuery.shouldRefreshIdentityMapResult());
        query.setCascadePolicy(sourceQuery.getCascadePolicy());
        query.setShouldMaintainCache(sourceQuery.shouldMaintainCache());
        // For flashback.
        if (((ObjectLevelReadQuery) sourceQuery).hasAsOfClause()) {
          query.setAsOfClause(((ObjectLevelReadQuery) sourceQuery).getAsOfClause());
        }

        // CR #4365 - used to prevent infinit recursion on refresh object cascade all
        query.setQueryId(sourceQuery.getQueryId());
      }

      return getIndirectionPolicy().valueFromQuery(query, row, executionSession);
    } else {
      return super.valueFromRow(row, joinManager, sourceQuery, executionSession);
    }
  }
 /** INTERNAL: Get a value from the object and set that in the respective field of the row. */
 protected void writeFromNullObjectIntoRow(AbstractRecord record) {
   if (isReadOnly()) {
     return;
   }
   if (isForeignKeyRelationship()) {
     Enumeration foreignKeys = getForeignKeyFields().elements();
     while (foreignKeys.hasMoreElements()) {
       record.put((DatabaseField) foreignKeys.nextElement(), null);
     }
   }
   if (getTypeField() != null) {
     record.put(getTypeField(), null);
   }
 }
  /** INTERNAL: Write fields needed for insert into the template for with null values. */
  public void writeInsertFieldsIntoRow(AbstractRecord record, AbstractSession session) {
    if (isReadOnly()) {
      return;
    }

    record.put(getField(), null);
  }
  /**
   * INTERNAL: Return the value of the field from the row or a value holder on the query to obtain
   * the object. Check for batch + aggregation reading.
   */
  public Object valueFromRow(
      AbstractRecord row,
      JoinedAttributeManager joinManager,
      ObjectBuildingQuery query,
      AbstractSession executionSession)
      throws DatabaseException {
    Ref ref = (Ref) row.get(getField());

    if (ref == null) {
      return null;
    }

    Struct struct;
    try {
      ((DatabaseAccessor) executionSession.getAccessor()).incrementCallCount(executionSession);
      java.sql.Connection connection =
          ((DatabaseAccessor) executionSession.getAccessor()).getConnection();
      struct =
          (Struct) executionSession.getPlatform().getRefValue(ref, executionSession, connection);
    } catch (java.sql.SQLException exception) {
      throw DatabaseException.sqlException(exception, executionSession, false);
    }
    AbstractRecord targetRow =
        ((ObjectRelationalDataTypeDescriptor) getReferenceDescriptor())
            .buildRowFromStructure(struct);
    ((DatabaseAccessor) executionSession.getAccessor()).decrementCallCount();

    return getReferenceDescriptor().getObjectBuilder().buildObject(query, targetRow, joinManager);
  }
  /**
   * 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.
   */
  public void writeFromObjectIntoRowForShallowInsertWithChangeRecord(
      ChangeRecord changeRecord, AbstractRecord record, AbstractSession session) {
    if (isReadOnly()) {
      return;
    }

    record.put(getField(), null);
  }
  /** INTERNAL: Get a value from the object and set that in the respective field of the row. */
  @Override
  public void writeFromObjectIntoRowForWhereClause(
      ObjectLevelModifyQuery query, AbstractRecord record) {
    if (isReadOnly()) {
      return;
    }
    Object object;
    if (query.isDeleteObjectQuery()) {
      object = query.getObject();
    } else {
      object = query.getBackupClone();
    }
    Object referenceObject = getRealAttributeValueFromObject(object, query.getSession());

    if (referenceObject == null) {
      writeFromNullObjectIntoRow(record);
    } else {
      if (isForeignKeyRelationship()) {
        Enumeration sourceFields = getForeignKeyFields().elements();
        ClassDescriptor descriptor = query.getSession().getDescriptor(referenceObject.getClass());
        while (sourceFields.hasMoreElements()) {
          DatabaseField sourceKey = (DatabaseField) sourceFields.nextElement();
          String targetQueryKey = (String) getSourceToTargetQueryKeyNames().get(sourceKey);
          DatabaseField targetKeyField =
              descriptor.getObjectBuilder().getFieldForQueryKeyName(targetQueryKey);
          if (targetKeyField == null) {
            throw DescriptorException.variableOneToOneMappingIsNotDefinedProperly(
                this, descriptor, targetQueryKey);
          }
          Object referenceValue =
              descriptor
                  .getObjectBuilder()
                  .extractValueFromObjectForField(
                      referenceObject, targetKeyField, query.getSession());
          record.put(sourceKey, referenceValue);
        }
      }
      if (getTypeField() != null) {
        record.put(getTypeField(), getTypeForImplementor(referenceObject.getClass()));
      }
    }
  }
  /** INTERNAL: Get a value from the object and set that in the respective field of the row. */
  public void writeFromObjectIntoRow(
      Object object, AbstractRecord record, AbstractSession session) {
    if (isReadOnly()) {
      return;
    }

    Object referenceObject = getRealAttributeValueFromObject(object, session);

    if (referenceObject == null) {
      // Fix for 2730536, must put something in modify row, even if it is null.
      record.put(getField(), null);
      return;
    }

    Ref ref =
        ((ObjectRelationalDataTypeDescriptor) getReferenceDescriptor())
            .getRef(referenceObject, session);

    record.put(getField(), ref);
  }
  /**
   * INTERNAL: Get a value from the object and set that in the respective field of the row. If the
   * mapping id target foreign key, you must only write the type into the roe, the rest will be
   * updated when the object itself is written
   */
  @Override
  public void writeFromObjectIntoRowWithChangeRecord(
      ChangeRecord changeRecord, AbstractRecord record, AbstractSession session) {
    if (isReadOnly()) {
      return;
    }

    ObjectChangeSet changeSet =
        (ObjectChangeSet) ((ObjectReferenceChangeRecord) changeRecord).getNewValue();
    if (changeSet == null) {
      writeFromNullObjectIntoRow(record);
    } else {
      Object referenceObject = changeSet.getUnitOfWorkClone();
      if (isForeignKeyRelationship()) {
        Enumeration sourceFields = getForeignKeyFields().elements();
        ClassDescriptor descriptor = session.getDescriptor(referenceObject.getClass());
        while (sourceFields.hasMoreElements()) {
          DatabaseField sourceKey = (DatabaseField) sourceFields.nextElement();
          String targetQueryKey = (String) getSourceToTargetQueryKeyNames().get(sourceKey);
          DatabaseField targetKeyField =
              descriptor.getObjectBuilder().getFieldForQueryKeyName(targetQueryKey);
          if (targetKeyField == null) {
            throw DescriptorException.variableOneToOneMappingIsNotDefinedProperly(
                this, descriptor, targetQueryKey);
          }
          Object referenceValue =
              descriptor
                  .getObjectBuilder()
                  .extractValueFromObjectForField(referenceObject, targetKeyField, session);
          record.put(sourceKey, referenceValue);
        }
      }
      if (getTypeField() != null) {
        record.put(getTypeField(), getTypeForImplementor(referenceObject.getClass()));
      }
    }
  }
  /** INTERNAL: Get a value from the object and set that in the respective field of the row. */
  public void writeFromObjectIntoRowWithChangeRecord(
      ChangeRecord changeRecord, AbstractRecord record, AbstractSession session) {
    if (isReadOnly()) {
      return;
    }

    ObjectChangeSet changeSet =
        (ObjectChangeSet) ((ObjectReferenceChangeRecord) changeRecord).getNewValue();
    Object referenceObject = changeSet.getUnitOfWorkClone();

    if (referenceObject == null) {
      return;
    }

    Ref ref =
        ((ObjectRelationalDataTypeDescriptor) getReferenceDescriptor())
            .getRef(referenceObject, session);

    record.put(getField(), ref);
  }