oracle.olapi.syntax
Class OrderByElement

java.lang.Object
  oracle.olapi.syntax.SyntaxObject
      oracle.olapi.syntax.DataObject
          oracle.olapi.syntax.OrderByElement

public final class OrderByElement
extends DataObject

A DataObject that represents an expression of an OrderByClause.

See Also:

OrderByClause

Constructor Summary

OrderByElement(TypedExpression expression, boolean ascending, boolean nullsFirst)
Creates an OrderByElement with the specified expression and characteristics.

Method Summary

TypedExpression	getExpression() Gets the expression of this OrderByElement.
boolean	isAscending() Indicates whether the ordering sequence is ascending.
boolean	isCompositeObject() Indicates whether this OrderByElement contains other SyntaxObject objects.
boolean	isDescending() Indicates whether the ordering sequence is descending.
boolean	isNullsFirst() Indicates whether returned rows containing null values should appear first in the ordering sequence.
boolean	isNullsLast() Indicates whether returned rows containing null values should appear last in the ordering sequence.
java.lang.Object	visit(SyntaxObjectVisitor visitor, java.lang.Object context) Calls the visitOrderByElement method of the SyntaxObjectVisitor and passes that method this OrderByElement and an Object.

Methods inherited from class oracle.olapi.syntax.SyntaxObject

equals, equals, fromSyntax, fromSyntax, fromSyntax, fromSyntax, fromSyntax, isValid, toSyntax, toSyntax, toSyntax, toSyntax, toSyntax, toSyntax

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

OrderByElement

public OrderByElement(TypedExpression expression,
                      boolean ascending,
                      boolean nullsFirst)

Creates an OrderByElement with the specified expression and characteristics.

Parameters:

expression - A TypedExpression that represents an expression of an OrderByClause.

ascending - A boolean that is true if the sequence of the results for the expression should be in ascending order or false if they should be in descending order.

nullsFirst - A boolean that is true if null values should appear first in the sequence of the results for the expression or false if they should appear last.

Method Detail

visit

public java.lang.Object visit(SyntaxObjectVisitor visitor,
                              java.lang.Object context)

Calls the visitOrderByElement method of the SyntaxObjectVisitor and passes that method this OrderByElement and an Object.

Specified by:

visit in class SyntaxObject

Parameters:

visitor - A SyntaxObjectVisitor.

context - An Object.

Returns:

The Object returned by the visitOrderByElement method.

getExpression

public TypedExpression getExpression()

Gets the expression of this OrderByElement.

Returns:

A TypedExpression that evaluates to an expression of a SQL ORDER BY clause.

isAscending

public boolean isAscending()

Indicates whether the ordering sequence is ascending.

Returns:

A boolean that is true is the ordering sequence is ascending or false if it is not.

isDescending

public boolean isDescending()

Indicates whether the ordering sequence is descending.

Returns:

A boolean that is true is the ordering sequence is descending or false if it is not.

isNullsFirst

public boolean isNullsFirst()

Indicates whether returned rows containing null values should appear first in the ordering sequence.

Returns:

A boolean that is true if null values should appear first in the ordering sequence or false if they should not.

isNullsLast

public boolean isNullsLast()

Indicates whether returned rows containing null values should appear last in the ordering sequence.

Returns:

A boolean that is true if null values should appear last in the ordering sequence or false if they should not.

isCompositeObject

public boolean isCompositeObject()

Indicates whether this OrderByElement contains other SyntaxObject objects. Because an OrderByElement contains a TypedExpression, this method returns true.

Returns:

A boolean that is true.