org.eclipse.persistence.jpa.jpql

Interface JPQLQueryDeclaration

All Known Implementing Classes:

AbstractRangeDeclaration, CollectionDeclaration, Declaration, DerivedDeclaration, RangeDeclaration, SubqueryDeclaration, TableDeclaration, UnknownDeclaration

public interface JPQLQueryDeclaration

A JPQLQueryDeclaration represents either an identification variable declaration or a collection member declaration. For a subquery, the declaration can be a derived path expression.

Provisional API: This interface is part of an interim API that is still under development and expected to change significantly before reaching stability. It is available at this early stage to solicit feedback from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken (repeatedly) as the API evolves.

Version:

2.5

Author:

Pascal Filion

Since:

2.4

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	JPQLQueryDeclaration.Type This enum type defines the various types of declarations supported by both the JPA functional specification and EclipseLink.

Method Summary

Modifier and Type	Method and Description
Expression	getBaseExpression() Returns the range variable declaration if this is a range declaration otherwise the collection-valued path expression when this is a collection member declaration.
Expression	getDeclarationExpression() Returns the declaration expression, which is either an IdentificationVariableDeclaration or a CollectionMemberDeclaration when part of a FROM clause, otherwise it's either the DeleteClause or the UpdateClause.
java.util.List<Join>	getJoins() Returns the JOIN expressions defined with this declaration, if supported.
JPQLQueryDeclaration.Type	getType() Determines the type this declaration represents.
java.lang.String	getVariableName() Returns the identification variable name that is defining either the abstract schema name or the collection-valued path expression
boolean	hasJoins() Determines whether the declaration contains JOIN expressions.

Method Detail

getBaseExpression

Expression getBaseExpression()

Returns the range variable declaration if this is a range declaration otherwise the collection-valued path expression when this is a collection member declaration.

Returns:

Either the range variable declaration or the collection-valued path expression

getDeclarationExpression

Expression getDeclarationExpression()

Returns the declaration expression, which is either an IdentificationVariableDeclaration or a CollectionMemberDeclaration when part of a FROM clause, otherwise it's either the DeleteClause or the UpdateClause.

Returns:

The root of the declaration expression

getJoins

java.util.List<Join> getJoins()

Returns the JOIN expressions defined with this declaration, if supported. The list contains the JOIN expressions in ordered they were declared.

Returns:

The JOIN expressions defined with this declaration or an empty list if this declaration does not support it

getType

JPQLQueryDeclaration.Type getType()

Determines the type this declaration represents.

Returns:

One of the possible types

getVariableName

java.lang.String getVariableName()

Returns the identification variable name that is defining either the abstract schema name or the collection-valued path expression

Returns:

The identification variable or an empty string if none was defined

hasJoins

boolean hasJoins()

Determines whether the declaration contains JOIN expressions. This can be true only when JPQLQueryDeclaration.Type.isRange() returns true. A collection member declaration does not have JOIN expressions.

Returns:

true if at least one JOIN expression was parsed; otherwise false