Expression (EclipseLink 2.6.8, API Reference)

Type Parameters:
T - the type of the expression

All Superinterfaces:

Selection<T>, TupleElement<T>

All Known Subinterfaces:

CollectionJoin<Z,E>, CriteriaBuilder.Case<R>, CriteriaBuilder.Coalesce<T>, CriteriaBuilder.In<T>, CriteriaBuilder.SimpleCase<C,R>, From<Z,X>, Join<Z,X>, ListJoin<Z,E>, MapJoin<Z,K,V>, ParameterExpression<T>, Path<X>, PluralJoin<Z,C,E>, Predicate, Root<X>, SetJoin<Z,E>, Subquery<T>
```
public interface Expression<T>
extends Selection<T>
```
Type for query expressions.

Since:

Java Persistence 2.0

Method Summary

Methods
Modifier and Type	Method and Description
`<X> Expression<X>`	`as(java.lang.Class<X> type)` Perform a typecast upon the expression, returning a new expression object.
`Predicate`	`in(java.util.Collection<?> values)` Create a predicate to test whether the expression is a member of the collection.
`Predicate`	`in(Expression<?>... values)` Create a predicate to test whether the expression is a member of the argument list.
`Predicate`	`in(Expression<java.util.Collection<?>> values)` Create a predicate to test whether the expression is a member of the collection.
`Predicate`	`in(java.lang.Object... values)` Create a predicate to test whether the expression is a member of the argument list.
`Predicate`	`isNotNull()` Create a predicate to test whether the expression is not null.
`Predicate`	`isNull()` Create a predicate to test whether the expression is null.

Methods inherited from interface javax.persistence.criteria.Selection
alias, getCompoundSelectionItems, isCompoundSelection

Methods inherited from interface javax.persistence.TupleElement
getAlias, getJavaType

- Method Detail
  - isNull
```
Predicate isNull()
```
    Create a predicate to test whether the expression is null.
    
    Returns:
    predicate testing whether the expression is null
  - isNotNull
```
Predicate isNotNull()
```
    Create a predicate to test whether the expression is not null.
    
    Returns:
    predicate testing whether the expression is not null
  - in
```
Predicate in(java.lang.Object... values)
```
    Create a predicate to test whether the expression is a member of the argument list.
    
    Parameters:
    values - values to be tested against
    
    Returns:
    predicate testing for membership
  - in
```
Predicate in(Expression<?>... values)
```
    Create a predicate to test whether the expression is a member of the argument list.
    
    Parameters:
    values - expressions to be tested against
    
    Returns:
    predicate testing for membership
  - in
```
Predicate in(java.util.Collection<?> values)
```
    Create a predicate to test whether the expression is a member of the collection.
    
    Parameters:
    values - collection of values to be tested against
    
    Returns:
    predicate testing for membership
  - in
```
Predicate in(Expression<java.util.Collection<?>> values)
```
    Create a predicate to test whether the expression is a member of the collection.
    
    Parameters:
    values - expression corresponding to collection to be tested against
    
    Returns:
    predicate testing for membership
  - as
```
<X> Expression<X> as(java.lang.Class<X> type)
```
    Perform a typecast upon the expression, returning a new expression object. This method does not cause type conversion: the runtime type is not changed. Warning: may result in a runtime failure.
    
    Parameters:
    type - intended type of the expression
    
    Returns:
    new expression of the given type

Interface Expression<T>

Method Summary

Methods inherited from interface javax.persistence.criteria.Selection

Methods inherited from interface javax.persistence.TupleElement

Method Detail

isNull

isNotNull

in

in

in

in

as