org.eclipse.persistence.jpa.jpql.model.query
Class TypeExpressionStateObject

java.lang.Object
  org.eclipse.persistence.jpa.jpql.model.query.AbstractStateObject
      org.eclipse.persistence.jpa.jpql.model.query.AbstractEncapsulatedExpressionStateObject
          org.eclipse.persistence.jpa.jpql.model.query.AbstractSingleEncapsulatedExpressionStateObject
              org.eclipse.persistence.jpa.jpql.model.query.TypeExpressionStateObject

All Implemented Interfaces:

StateObject

public class TypeExpressionStateObject
extends AbstractSingleEncapsulatedExpressionStateObject

An entity type expression can be used to restrict query polymorphism. The TYPE operator returns the exact type of the argument.

Part of JPA 2.0.

BNF: type_discriminator ::= TYPE(identification_variable | single_valued_object_path_expression | input_parameter)

Version:

2.4

See Also:

TypeExpression

Author:

Pascal Filion

Since:

2.4

Field Summary

Fields inherited from class org.eclipse.persistence.jpa.jpql.model.query.AbstractSingleEncapsulatedExpressionStateObject

STATE_OBJECT_PROPERTY

Constructor Summary

TypeExpressionStateObject(StateObject parent)
Creates a new TypeExpressionStateObject.

TypeExpressionStateObject(StateObject parent, StateObject stateObject)
Creates a new TypeExpressionStateObject.

TypeExpressionStateObject(StateObject parent, java.lang.String path)
Creates a new TypeExpressionStateObject.

Method Summary

void	accept(StateObjectVisitor visitor) Visits this StateObject by the given visitor.
TypeExpression	getExpression() Returns the actual parsed object if this StateObject representation of the JPQL query was created by parsing an existing JPQL query.
java.lang.String	getIdentifier() Returns the JPQL identifier of the expression represented by this AbstractSingleEncapsulatedExpressionStateObject.
protected java.lang.String	getQueryBNFId() Returns the unique identifier of the JPQLQueryBNF that will determine how to parse the encapsulated expression.
void	setExpression(TypeExpression expression) Keeps a reference of the parsed object object, which should only be done when this object is instantiated during the conversion of a parsed JPQL query into StateObjects.
void	setStateObject(StateObject stateObject) Sets the given StateObject to represent the new encapsulated expression.

Methods inherited from class org.eclipse.persistence.jpa.jpql.model.query.AbstractSingleEncapsulatedExpressionStateObject

addChildren, getStateObject, hasStateObject, isEquivalent, parse, toTextEncapsulatedExpression

Methods inherited from class org.eclipse.persistence.jpa.jpql.model.query.AbstractEncapsulatedExpressionStateObject

toTextInternal

Methods inherited from class org.eclipse.persistence.jpa.jpql.model.query.AbstractStateObject

acceptUnknownVisitor, acceptUnknownVisitor, addProblems, addPropertyChangeListener, areEquivalent, buildProblem, buildProblem, buildStateObject, buildStateObjects, checkParent, children, decorate, equals, findIdentificationVariable, firePropertyChanged, getChangeSupport, getDeclaration, getDecorator, getGrammar, getManagedTypeProvider, getParent, getQueryBuilder, getRoot, getType, getType, getTypeHelper, getTypeRepository, hashCode, initialize, isDecorated, parent, parent, parent, removePropertyChangeListener, setExpression, setParent, toString, toString, toStringInternal, toStringItems, toText

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

TypeExpressionStateObject

public TypeExpressionStateObject(StateObject parent)

Creates a new TypeExpressionStateObject.

Parameters:

parent - The parent of this state object, which cannot be null

Throws:

java.lang.NullPointerException - The given parent cannot be null

TypeExpressionStateObject

public TypeExpressionStateObject(StateObject parent,
                                 StateObject stateObject)

Creates a new TypeExpressionStateObject.

Parameters:

parent - The parent of this state object, which cannot be null

stateObject - The StateObject representing the encapsulated expression

Throws:

java.lang.NullPointerException - The given parent cannot be null

TypeExpressionStateObject

public TypeExpressionStateObject(StateObject parent,
                                 java.lang.String path)

Creates a new TypeExpressionStateObject.

Parameters:

parent - The parent of this state object, which cannot be null

path - Either the identification variable, the singled-valued object path expression or the input parameter

Throws:

java.lang.NullPointerException - The given parent cannot be null

Method Detail

accept

public void accept(StateObjectVisitor visitor)

Visits this StateObject by the given visitor.

Parameters:

visitor - The visitor to visit this object

getExpression

public TypeExpression getExpression()

Returns the actual parsed object if this StateObject representation of the JPQL query was created by parsing an existing JPQL query.

Specified by:

getExpression in interface StateObject

Overrides:

getExpression in class AbstractSingleEncapsulatedExpressionStateObject

Returns:

The parsed object when a JPQL query is parsed and converted into a StateObject or null when the JPQL query is manually created (i.e. not from a string)

getIdentifier

public java.lang.String getIdentifier()

Returns the JPQL identifier of the expression represented by this AbstractSingleEncapsulatedExpressionStateObject.

Specified by:

getIdentifier in class AbstractEncapsulatedExpressionStateObject

Returns:

The JPQL identifier that is shown before the left parenthesis

getQueryBNFId

protected java.lang.String getQueryBNFId()

Returns the unique identifier of the JPQLQueryBNF that will determine how to parse the encapsulated expression.

Specified by:

getQueryBNFId in class AbstractSingleEncapsulatedExpressionStateObject

Returns:

The non-null ID of the BNF

setExpression

public void setExpression(TypeExpression expression)

Keeps a reference of the parsed object object, which should only be done when this object is instantiated during the conversion of a parsed JPQL query into StateObjects.

Parameters:

expression - The parsed object representing a TYPE expression

setStateObject

public void setStateObject(StateObject stateObject)

Sets the given StateObject to represent the new encapsulated expression.

Overrides:

setStateObject in class AbstractSingleEncapsulatedExpressionStateObject

Parameters:

stateObject - The new encapsulated StateObject