Package javax.jdo.query
Interface Expression<T>
- Type Parameters:
T
- Java type being represented here
- All Known Subinterfaces:
BooleanExpression
,ByteExpression
,CharacterExpression
,CollectionExpression<T,
,E> ComparableExpression<T>
,DateExpression
,DateTimeExpression
,EnumExpression<T>
,GeometryCollectionExpression<T>
,GeometryExpression<T>
,IfThenElseExpression<T>
,LinearRingExpression<T>
,LineStringExpression<T>
,ListExpression<T,
,E> LocalDateExpression
,LocalDateTimeExpression
,LocalTimeExpression
,MapExpression<T,
,K, V> MultiLineStringExpression<T>
,MultiPointExpression<T>
,MultiPolygonExpression<T>
,NumericExpression<T>
,ObjectExpression<T>
,OptionalExpression<T>
,PersistableExpression<T>
,PointExpression<T>
,PolygonExpression<T>
,StringExpression
,TimeExpression
public interface Expression<T>
Representation of an expression in a query.
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Method Summary
Modifier and TypeMethodDescriptionMethod to set the alias for this expression when used in the result clause.Return an expression where this expression is cast to the specified type.count()
Method to return a numeric expression representing the aggregated count of this expression.Method to return a numeric expression representing the aggregated (distinct) count of this expression.eq
(Expression expr) Method returning whether this expression equals the other expression.Method returning whether this expression equals the literal.instanceOf
(Class cls) Return an expression for whether this expression is an instanceof the supplied class.ne
(Expression expr) Method returning whether this expression doesn't equal the other expression.Method returning whether this expression doesn't equal the literal.
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Method Details
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as
Method to set the alias for this expression when used in the result clause.- Parameters:
alias
- The alias- Returns:
- This expression
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eq
Method returning whether this expression equals the other expression.- Parameters:
expr
- Other expression- Returns:
- Whether they are equal
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eq
Method returning whether this expression equals the literal.- Parameters:
t
- Literal- Returns:
- Whether they are equal
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ne
Method returning whether this expression doesn't equal the other expression.- Parameters:
expr
- Other expression- Returns:
- Whether they are not equal
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ne
Method returning whether this expression doesn't equal the literal.- Parameters:
t
- literal- Returns:
- Whether they are not equal
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count
NumericExpression<Long> count()Method to return a numeric expression representing the aggregated count of this expression.- Returns:
- Numeric expression for the count
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countDistinct
NumericExpression<Long> countDistinct()Method to return a numeric expression representing the aggregated (distinct) count of this expression.- Returns:
- Numeric expression for the distinct count
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instanceOf
Return an expression for whether this expression is an instanceof the supplied class.- Parameters:
cls
- Class to check against- Returns:
- Whether it is an instanceof
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cast
Return an expression where this expression is cast to the specified type.- Parameters:
cls
- Class to cast to- Returns:
- The cast expression
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