java.lang.Object
- org.eclipse.persistence.jpa.jpql.parser.AbstractExpression
- - org.eclipse.persistence.jpa.jpql.parser.OrderByItem

All Implemented Interfaces:

Expression
```
public final class OrderByItem
extends AbstractExpression
```
An orderby_item must be one of the following:
1. A state_field_path_expression that evaluates to an orderable state field of an entity or embeddable class abstract schema type designated in the SELECT clause by one of the following:
  - A general_identification_variable
  - A single_valued_object_path_expression
2. A state_field_path_expression that evaluates to the same state field of the same entity or embeddable abstract schema type as a state_field_path_expression in the SELECT clause
3. A result_variable that refers to an orderable item in the SELECT clause for which the same result_variable has been specified. This may be the result of an aggregate_expression, a scalar_expression, or a state_field_path_expression in the SELECT clause.
The keyword ASC specifies that ascending ordering be used for the associated orderby_item; the keyword DESC specifies that descending ordering be used. Ascending ordering is the default.
The keyword NULLS FIRST specifies that nulls first ordering be used for the associated orderby_item; the keyword NULLS LAST specifies that nulls last ordering be used. Ascending ordering is the default.
JPA 1.0:
BNF: orderby_item ::= state_field_path_expression [ ASC | DESC ]

JPA 2.0
BNF: orderby_item ::= state_field_path_expression | result_variable [ ASC | DESC ]

EclipseLink 2.4:
BNF: orderby_item ::= state_field_path_expression | result_variable [ ASC | DESC ] [ NULLS FIRST | NULLS LAST ]
Since:

2.3

Version:

2.5

Author:

Pascal Filion

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`OrderByItem.NullOrdering`	This enumeration lists all the possible choices for ordering nulls in an item.
`static class`	`OrderByItem.Ordering`	This enumeration lists all the possible choices for ordering an item.

Field Summary
- Fields inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression
  COMMA, DOT, DOUBLE_QUOTE, LEFT_CURLY_BRACKET, LEFT_PARENTHESIS, NOT_DEFINED, RIGHT_CURLY_BRACKET, RIGHT_PARENTHESIS, SINGLE_QUOTE, SPACE, UNDERSCORE
- Fields inherited from interface org.eclipse.persistence.jpa.jpql.parser.Expression
  ABS, ALL, AND, ANY, AS, AS_OF, ASC, AVG, BETWEEN, BIT_LENGTH, BOTH, CASE, CAST, CHAR_LENGTH, CHARACTER_LENGTH, CLASS, COALESCE, COLUMN, CONCAT, CONNECT_BY, COUNT, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, DELETE, DELETE_FROM, DESC, DIFFERENT, DISTINCT, DIVISION, ELSE, EMPTY, END, ENTRY, EQUAL, ESCAPE, EXCEPT, EXISTS, EXTRACT, FALSE, FETCH, FIRST, FROM, FUNC, FUNCTION, GREATER_THAN, GREATER_THAN_OR_EQUAL, GROUP_BY, HAVING, IN, INDEX, INNER, INNER_JOIN, INNER_JOIN_FETCH, INTERSECT, IS, IS_EMPTY, IS_NOT_EMPTY, IS_NOT_NULL, IS_NULL, JOIN, JOIN_FETCH, KEY, LAST, LEADING, LEFT, LEFT_JOIN, LEFT_JOIN_FETCH, LEFT_OUTER_JOIN, LEFT_OUTER_JOIN_FETCH, LENGTH, LIKE, LOCATE, LOWER, LOWER_THAN, LOWER_THAN_OR_EQUAL, MAX, MEMBER, MEMBER_OF, MIN, MINUS, MOD, MULTIPLICATION, NAMED_PARAMETER, NEW, NOT, NOT_BETWEEN, NOT_EQUAL, NOT_EXISTS, NOT_IN, NOT_LIKE, NOT_MEMBER, NOT_MEMBER_OF, NULL, NULLIF, NULLS, NULLS_FIRST, NULLS_LAST, OBJECT, OF, ON, OPERATOR, OR, ORDER_BY, ORDER_SIBLINGS_BY, OUTER, PLUS, POSITION, POSITIONAL_PARAMETER, QUOTE, REGEXP, SCN, SELECT, SET, SIZE, SOME, SQL, SQRT, START_WITH, SUBSTRING, SUM, TABLE, THEN, TIMESTAMP, TRAILING, TREAT, TRIM, TRUE, TYPE, UNION, UNKNOWN, UPDATE, UPPER, VALUE, WHEN, WHERE

Constructor Summary

Constructors
Constructor Description

OrderByItem(AbstractExpression parent)
Creates a new OrderByItem.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`accept(ExpressionVisitor visitor)`	Visits this `Expression` by the given `visitor`.
`void`	`acceptChildren(ExpressionVisitor visitor)`	Visits the children of this `Expression`.
`JPQLQueryBNF`	`findQueryBNF(Expression expression)`	Retrieves the `JPQLQueryBNF` that represents the fragment of this `Expression` that was used when parsing the given `Expression`.
`String`	`getActualNullOrdering()`	Returns the actual `null` ordering identifier found in the string representation of the JPQL query, which has the actual case that was used.
`String`	`getActualOrdering()`	Returns the actual ordering identifier found in the string representation of the JPQL query, which has the actual case that was used.
`Expression`	`getExpression()`	Returns the `Expression` that represents the order by expression.
`OrderByItem.NullOrdering`	`getNullOrdering()`	Returns the enum constant representing the null ordering type.
`OrderByItem.Ordering`	`getOrdering()`	Returns the enum constant representing the ordering type.
`JPQLQueryBNF`	`getQueryBNF()`	Returns the BNF of this `Expression`.
`boolean`	`hasExpression()`	Determines whether the order by expression was parsed.
`boolean`	`hasNulls()`	Determines whether the `NULLS` identifier was parsed.
`boolean`	`hasOrdering()`	Determines whether `ASC` or `DESC` was parsed.
`boolean`	`hasSpaceAfterExpression()`	Determines whether a whitespace was parsed after the order by expression.
`boolean`	`hasSpaceAfterNulls()`	Determines whether a whitespace was parsed after the `NULLS` identifier.
`boolean`	`hasSpaceAfterOrdering()`	Determines whether a whitespace was parsed after the ordering.
`boolean`	`isAscending()`	Determines whether the ordering was specified as being ascendant.
`boolean`	`isDefault()`	Determines whether the ordering was not specified.
`boolean`	`isDescending()`	Determines whether the ordering was specified as being descendant.
`boolean`	`isNullsFirst()`	Determines whether the ordering was specified as being nulls first.
`boolean`	`isNullsLast()`	Determines whether the ordering was specified as being nulls first.

Methods inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression
children, getGrammar, getIdentifierVersion, getLength, getOffset, getParent, getQueryBNF, getRoot, isAncestor, orderedChildren, populatePosition, toActualText, toParsedText, toString

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - OrderByItem
```
public OrderByItem(AbstractExpression parent)
```
    Creates a new OrderByItem.
    
    Parameters:
    
    parent - The parent of this expression
- Method Detail
  - accept
```
public void accept(ExpressionVisitor visitor)
```
    Visits this Expression by the given visitor.
    
    Parameters:
    
    visitor - The ExpressionVisitor to visit this object
  - acceptChildren
```
public void acceptChildren(ExpressionVisitor visitor)
```
    Visits the children of this Expression. This method can be used to optimize traversing the children since a new list is not created every time Expression.children() is called.
    This does not traverse the Expression sub-hierarchy, use a subclass of AbstractTraverseChildrenVisitor in order to traverse the entire sub-hierarchy.
    
    Parameters:
    
    visitor - The visitor to visit the children of this object.
  - findQueryBNF
```
public JPQLQueryBNF findQueryBNF(Expression expression)
```
    Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.
    
    Specified by:
    
    findQueryBNF in interface Expression
    
    Overrides:
    
    findQueryBNF in class AbstractExpression
    
    Parameters:
    
    expression - The Expression that is a descendant of this one
    
    Returns:
    
    The JPQLQueryBNF that was used to parse the given expression
  - getActualNullOrdering
```
public String getActualNullOrdering()
```
    Returns the actual null ordering identifier found in the string representation of the JPQL query, which has the actual case that was used.
    
    Returns:
    
    The null ordering identifier that was actually parsed, if one was present, otherwise an empty string is returned
  - getActualOrdering
```
public String getActualOrdering()
```
    Returns the actual ordering identifier found in the string representation of the JPQL query, which has the actual case that was used.
    
    Returns:
    
    The ordering identifier that was actually parsed, if one was present, otherwise an empty string is returned
  - getExpression
```
public Expression getExpression()
```
    Returns the Expression that represents the order by expression.
    
    Returns:
    
    The expression that was parsed representing the order by expression
  - getNullOrdering
```
public OrderByItem.NullOrdering getNullOrdering()
```
    Returns the enum constant representing the null ordering type.
    
    Returns:
    
    The constant representing the null ordering, in the case the ordering was not parsed, then OrderByItem.NullOrdering.DEFAULT is returned
  - getOrdering
```
public OrderByItem.Ordering getOrdering()
```
    Returns the enum constant representing the ordering type.
    
    Returns:
    
    The constant representing the ordering, in the case the ordering was not parsed, then OrderByItem.Ordering.DEFAULT is returned
  - getQueryBNF
```
public JPQLQueryBNF getQueryBNF()
```
    Returns the BNF of this Expression.
    
    Returns:
    
    The JPQLQueryBNF, which represents the grammar of this Expression
  - hasExpression
```
public boolean hasExpression()
```
    Determines whether the order by expression was parsed.
    
    Returns:
    
    true if the order by expression was parsed; false otherwise
  - hasNulls
```
public boolean hasNulls()
```
    Determines whether the NULLS identifier was parsed.
    
    Returns:
    
    true if the NULLS identifier was parsed; false otherwise
  - hasOrdering
```
public boolean hasOrdering()
```
    Determines whether ASC or DESC was parsed.
    
    Returns:
    
    true if the ordering status was parsed; false otherwise
    
    Since:
    
    2.5
  - hasSpaceAfterExpression
```
public boolean hasSpaceAfterExpression()
```
    Determines whether a whitespace was parsed after the order by expression.
    
    Returns:
    
    true if there was a whitespace after the order by expression; false otherwise
  - hasSpaceAfterNulls
```
public boolean hasSpaceAfterNulls()
```
    Determines whether a whitespace was parsed after the NULLS identifier. If the composite identifier was fully parsed - NULLS FIRST or NULLS LAST - then this is always true, but if only NULLS was parsed, then this can be useful to determine if there was a space after.
    
    Returns:
    
    true if there was a whitespace after the NULLS identifier; false otherwise
  - hasSpaceAfterOrdering
```
public boolean hasSpaceAfterOrdering()
```
    Determines whether a whitespace was parsed after the ordering.
    
    Returns:
    
    true if there was a whitespace after the ordering; false otherwise
  - isAscending
```
public boolean isAscending()
```
    Determines whether the ordering was specified as being ascendant.
    
    Returns:
    
    true if ASC was parsed; false otherwise
  - isDefault
```
public boolean isDefault()
```
    Determines whether the ordering was not specified.
    
    Returns:
    
    true if no ordering was parsed; false otherwise
  - isDescending
```
public boolean isDescending()
```
    Determines whether the ordering was specified as being descendant.
    
    Returns:
    
    true if DESC was parsed; false otherwise
  - isNullsFirst
```
public boolean isNullsFirst()
```
    Determines whether the ordering was specified as being nulls first.
    
    Returns:
    
    true if NULLS FIRST was parsed; false otherwise
  - isNullsLast
```
public boolean isNullsLast()
```
    Determines whether the ordering was specified as being nulls first.
    
    Returns:
    
    true if NULLS LAST was parsed; false otherwise

Class OrderByItem

Nested Class Summary

Field Summary

Fields inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression

Fields inherited from interface org.eclipse.persistence.jpa.jpql.parser.Expression

Constructor Summary

Method Summary

Methods inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression

Methods inherited from class java.lang.Object

Constructor Detail

OrderByItem

Method Detail

accept

acceptChildren

findQueryBNF

getActualNullOrdering

getActualOrdering

getExpression

getNullOrdering

getOrdering

getQueryBNF

hasExpression

hasNulls

hasOrdering

hasSpaceAfterExpression

hasSpaceAfterNulls

hasSpaceAfterOrdering

isAscending

isDefault

isDescending

isNullsFirst

isNullsLast