/**
   * INTERNAL: Returns the first field from each of the owned tables, used for fine-grained
   * pessimistic locking.
   */
  protected Vector getForUpdateOfFields() {
    Vector allFields = getFields();
    int expected = getTableAliases().size();
    Vector firstFields = new Vector(expected);
    DatabaseTable lastTable = null;
    DatabaseField field = null;
    int i = 0;

    // The following loop takes O(n*m) time.  n=# of fields. m=#tables.
    // However, in the m=1 case this will take one pass only.
    // Also assuming that fields are generally sorted by table, this will
    // take O(n) time.
    // An even faster way may be to go getDescriptor().getAdditionalPrimaryKeyFields.
    while ((i < allFields.size()) && (firstFields.size() < expected)) {
      field = (DatabaseField) allFields.elementAt(i++);
      if ((lastTable == null) || !field.getTable().equals(lastTable)) {
        lastTable = field.getTable();
        int j = 0;
        while (j < firstFields.size()) {
          if (lastTable.equals(((DatabaseField) firstFields.elementAt(j)).getTable())) {
            break;
          }
          j++;
        }
        if (j == firstFields.size()) {
          firstFields.addElement(field);
        }
      }
    }
    return firstFields;
  }
  /** INTERNAL: Print SQL onto the stream, using the ExpressionPrinter for context */
  public void printSQL(ExpressionSQLPrinter printer) {
    if (isAttribute()) {
      printer.printField(getAliasedField());
    }

    // If the mapping is a direct collection then this falls into a gray area.
    // It must be treated as an attribute at this moment for it has a direct field.
    // However it is not an attribute in the sense that it also represents a foreign
    // reference and a mapping criteria has been added.
    // For bug 2900974 these are now handled as non-attributes during normalize but
    // as attributes when printing SQL.
    //
    if ((!isAttribute()) && (getMapping() != null) && getMapping().isDirectCollectionMapping()) {
      DirectCollectionMapping directCollectionMapping = (DirectCollectionMapping) getMapping();

      // The aliased table comes for free as it was a required part of the join criteria.
      TableExpression table =
          (TableExpression) getTable(directCollectionMapping.getReferenceTable());
      DatabaseTable aliasedTable = table.aliasForTable(table.getTable());
      DatabaseField aliasedField = (DatabaseField) directCollectionMapping.getDirectField().clone();
      aliasedField.setTable(aliasedTable);
      printer.printField(aliasedField);
    }

    if ((getMapping() != null) && getMapping().isNestedTableMapping()) {
      DatabaseTable tableAlias = aliasForTable(new NestedTable(this));
      printer.printString(tableAlias.getName());
    }
  }
  /**
   * INTERNAL: This methods clones all the fields and ensures that each collection refers to the
   * same clones.
   */
  @Override
  public Object clone() {
    VariableOneToOneMapping clone = (VariableOneToOneMapping) super.clone();
    Map setOfKeys = new HashMap(getSourceToTargetQueryKeyNames().size());
    Map sourceToTarget = new HashMap(getSourceToTargetQueryKeyNames().size());
    Vector foreignKeys =
        org.eclipse.persistence.internal.helper.NonSynchronizedVector.newInstance(
            getForeignKeyFields().size());

    if (getTypeField() != null) {
      clone.setTypeField((DatabaseField) this.getTypeField().clone());
    }

    for (Iterator enumtr = getSourceToTargetQueryKeyNames().keySet().iterator();
        enumtr.hasNext(); ) {
      // Clone the SourceKeyFields
      DatabaseField field = (DatabaseField) enumtr.next();
      DatabaseField clonedField = (DatabaseField) field.clone();
      setOfKeys.put(field, clonedField);
      // on the next line I'm cloning the query key names
      sourceToTarget.put(clonedField, getSourceToTargetQueryKeyNames().get(field));
    }

    for (Enumeration enumtr = getForeignKeyFields().elements(); enumtr.hasMoreElements(); ) {
      DatabaseField field = (DatabaseField) enumtr.nextElement();
      foreignKeys.addElement(setOfKeys.get(field));
    }
    clone.setSourceToTargetQueryKeyFields(sourceToTarget);
    clone.setForeignKeyFields(foreignKeys);
    clone.setTypeIndicatorTranslation(new HashMap(this.getTypeIndicatorTranslation()));
    return clone;
  }
  /** Append the string containing the SQL insert string for the given table. */
  protected SQLCall buildCallWithoutReturning(AbstractSession session) {
    SQLCall call = new SQLCall();
    call.returnNothing();

    Writer writer = new CharArrayWriter(200);
    try {
      writer.write("INSERT ");
      if (getHintString() != null) {
        writer.write(getHintString());
        writer.write(" ");
      }
      writer.write("INTO ");
      writer.write(getTable().getQualifiedNameDelimited(session.getPlatform()));
      writer.write(" (");

      Vector fieldsForTable = new Vector();
      for (Enumeration fieldsEnum = getModifyRow().keys(); fieldsEnum.hasMoreElements(); ) {
        DatabaseField field = (DatabaseField) fieldsEnum.nextElement();
        if (field.getTable().equals(getTable()) || (!field.hasTableName())) {
          fieldsForTable.addElement(field);
        }
      }

      if (fieldsForTable.isEmpty()) {
        throw QueryException.objectToInsertIsEmpty(getTable());
      }

      for (int i = 0; i < fieldsForTable.size(); i++) {
        writer.write(
            ((DatabaseField) fieldsForTable.elementAt(i)).getNameDelimited(session.getPlatform()));
        if ((i + 1) < fieldsForTable.size()) {
          writer.write(", ");
        }
      }
      writer.write(") VALUES (");

      for (int i = 0; i < fieldsForTable.size(); i++) {
        DatabaseField field = (DatabaseField) fieldsForTable.elementAt(i);
        call.appendModify(writer, field);
        if ((i + 1) < fieldsForTable.size()) {
          writer.write(", ");
        }
      }
      writer.write(")");

      call.setSQLString(writer.toString());
    } catch (IOException exception) {
      throw ValidationException.fileError(exception);
    }
    return call;
  }
  /**
   * INTERNAL: Return the classification for the field contained in the mapping. This is used to
   * convert the row value to a consistent java value.
   */
  @Override
  public Class getFieldClassification(DatabaseField fieldToClassify) {
    if ((getTypeField() != null) && (fieldToClassify.equals(getTypeField()))) {
      return getTypeField().getType();
    }

    String queryKey = (String) getSourceToTargetQueryKeyNames().get(fieldToClassify);
    if (queryKey == null) {
      return null;
    }
    // Search any of the implementor descriptors for a mapping for the query-key.
    Iterator iterator =
        getReferenceDescriptor().getInterfacePolicy().getChildDescriptors().iterator();
    if (iterator.hasNext()) {
      ClassDescriptor firstChild = (ClassDescriptor) iterator.next();
      DatabaseMapping mapping = firstChild.getObjectBuilder().getMappingForAttributeName(queryKey);
      if ((mapping != null) && (mapping.isDirectToFieldMapping())) {
        return ((AbstractDirectMapping) mapping).getAttributeClassification();
      }
      QueryKey targetQueryKey = firstChild.getQueryKeyNamed(queryKey);
      if ((targetQueryKey != null) && (targetQueryKey.isDirectQueryKey())) {
        return firstChild
            .getObjectBuilder()
            .getFieldClassification(((DirectQueryKey) targetQueryKey).getField());
      }
    }
    return null;
  }
  /** INTERNAL: Alias the database field for our current environment */
  protected void initializeAliasedField() {
    DatabaseField tempField = (DatabaseField) getField().clone();
    DatabaseTable aliasedTable = getAliasedTable();

    //  Put in a special check here so that if the aliasing does nothing we don't cache the
    // result because it's invalid. This saves us from caching premature data if e.g. debugging
    // causes us to print too early"
    //	if (aliasedTable.equals(getField().getTable())) {
    //		return;
    //	} else {
    aliasedField = tempField;
    aliasedField.setTable(aliasedTable);
    //	}
  }
  /**
   * INTERNAL: Build and return the nested rows from the specified field value. This method allows
   * the field value to be an ARRAY containing other structures such as arrays or Struct, or direct
   * values.
   */
  public static Object buildContainerFromArray(
      Array fieldValue, ObjectRelationalDatabaseField arrayField, AbstractSession session)
      throws DatabaseException {
    if (arrayField.getType() == null) {
      return fieldValue;
    }
    Object[] objects = null;
    try {
      objects = (Object[]) fieldValue.getArray();
    } catch (java.sql.SQLException ex) {
      throw DatabaseException.sqlException(ex, session, false);
    }
    if (objects == null) {
      return null;
    }

    boolean isNestedStructure = false;
    ObjectRelationalDataTypeDescriptor ord = null;
    DatabaseField nestedType = null;
    if (arrayField != null) {
      nestedType = arrayField.getNestedTypeField();
      if ((nestedType != null) && nestedType.getSqlType() == Types.STRUCT) {
        ClassDescriptor descriptor = session.getDescriptor(nestedType.getType());
        if ((descriptor != null) && (descriptor.isObjectRelationalDataTypeDescriptor())) {
          // this is used to convert non-null objects passed through stored procedures and custom
          // SQL to structs
          ord = (ObjectRelationalDataTypeDescriptor) descriptor;
        }
      } else if ((nestedType != null) && (nestedType instanceof ObjectRelationalDatabaseField)) {
        isNestedStructure = true;
      }
    }
    // handle ARRAY conversions
    ReadObjectQuery query = new ReadObjectQuery();
    query.setSession(session);
    ContainerPolicy cp = ContainerPolicy.buildPolicyFor(arrayField.getType());
    Object container = cp.containerInstance(objects.length);
    for (int i = 0; i < objects.length; i++) {
      Object arrayValue = objects[i];
      if (arrayValue == null) {
        return null;
      }
      if (ord != null) {
        AbstractRecord nestedRow = ord.buildRowFromStructure((Struct) arrayValue);
        ClassDescriptor descriptor = ord;
        if (descriptor.hasInheritance()) {
          Class newElementClass =
              descriptor.getInheritancePolicy().classFromRow(nestedRow, session);
          if (!descriptor.getJavaClass().equals(newElementClass)) {
            descriptor = session.getDescriptor(newElementClass);
            if (descriptor == null) {
              descriptor = ord;
            }
          }
        }
        arrayValue = descriptor.getObjectBuilder().buildNewInstance();
        descriptor
            .getObjectBuilder()
            .buildAttributesIntoObject(arrayValue, nestedRow, query, null, false);
      } else if (isNestedStructure && (arrayValue instanceof Array)) {
        arrayValue =
            buildContainerFromArray(
                (Array) arrayValue, (ObjectRelationalDatabaseField) nestedType, session);
      }

      cp.addInto(arrayValue, container, session);
    }
    return container;
  }