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

java.lang.Object
  org.eclipse.persistence.jpa.jpql.model.query.AbstractStateObject
      org.eclipse.persistence.jpa.jpql.model.query.NullComparisonExpressionStateObject

All Implemented Interfaces:

StateObject

public class NullComparisonExpressionStateObject
extends AbstractStateObject

A null comparison tests whether or not the single-valued path expression or input parameter is a NULL value.

BNF: null_comparison_expression ::= {single_valued_path_expression | input_parameter} IS [NOT] NULL

Version:

2.4.2

See Also:

NullComparisonExpression

Author:

Pascal Filion

Since:

2.4

Field Summary

static java.lang.String	NOT_PROPERTY Notifies the visibility of the NOT identifier has changed.
static java.lang.String	STATE_OBJECT_PROPERTY Notifies the state object property has changed.

Constructor Summary

NullComparisonExpressionStateObject(StateObject parent)
Creates a new NullComparisonExpressionStateObject.

NullComparisonExpressionStateObject(StateObject parent, boolean not, StateObject stateObject)
Creates a new NullComparisonExpressionStateObject.

NullComparisonExpressionStateObject(StateObject parent, boolean not, java.lang.String path)
Creates a new NullComparisonExpressionStateObject.

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

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

Method Summary

void	accept(StateObjectVisitor visitor) Visits this StateObject by the given visitor.
protected void	addChildren(java.util.List<StateObject> children) Adds the children of this StateObject to the given list.
NullComparisonExpressionStateObject	addNot() Makes sure the NOT identifier is specified.
NullComparisonExpression	getExpression() Returns the actual parsed object if this StateObject representation of the JPQL query was created by parsing an existing JPQL query.
StateObject	getStateObject() Returns the StateObject representing the collection-valued path expression.
boolean	hasNot() Determines whether the NOT identifier is used or not.
boolean	hasStateObject() Determines whether there is a StateObject representing the collection-valued path expression.
boolean	isEquivalent(StateObject stateObject) Determines whether the given StateObject is equivalent to this one, i.e. the information of both StateObject is the same.
void	removeNot() Makes sure the NOT identifier is not specified.
void	setExpression(NullComparisonExpression 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	setNot(boolean not) Sets whether the NOT identifier should be part of the expression or not.
void	setStateObject(StateObject stateObject) Sets the given StateObject as the collection-valued path expression.
void	toggleNot() Changes the visibility state of the NOT identifier.
protected void	toTextInternal(java.lang.Appendable writer) Prints out a string representation of this StateObject, which should not be used to define a true string representation of a JPQL query but should be used for debugging purposes.

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

Field Detail

NOT_PROPERTY

public static java.lang.String NOT_PROPERTY

Notifies the visibility of the NOT identifier has changed.

STATE_OBJECT_PROPERTY

public static final java.lang.String STATE_OBJECT_PROPERTY

Notifies the state object property has changed.

See Also:

Constant Field Values

Constructor Detail

NullComparisonExpressionStateObject

public NullComparisonExpressionStateObject(StateObject parent)

Creates a new NullComparisonExpressionStateObject.

Parameters:

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

Throws:

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

NullComparisonExpressionStateObject

public NullComparisonExpressionStateObject(StateObject parent,
                                           boolean not,
                                           StateObject stateObject)

Creates a new NullComparisonExpressionStateObject.

Parameters:

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

not - Determines whether the NOT identifier is part of the expression or not

stateObject - The StateObject representing the collection-valued path expression

Throws:

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

NullComparisonExpressionStateObject

public NullComparisonExpressionStateObject(StateObject parent,
                                           boolean not,
                                           java.lang.String path)

Creates a new NullComparisonExpressionStateObject.

Parameters:

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

not - Determines whether the NOT identifier is part of the expression or not

path - Either the singled-valued path expression or the input parameter

Throws:

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

NullComparisonExpressionStateObject

public NullComparisonExpressionStateObject(StateObject parent,
                                           StateObject stateObject)

Creates a new NullComparisonExpressionStateObject.

Parameters:

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

stateObject - The StateObject representing the collection-valued path expression

Throws:

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

NullComparisonExpressionStateObject

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

Creates a new NullComparisonExpressionStateObject.

Parameters:

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

path - Either the singled-valued 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

addChildren

protected void addChildren(java.util.List<StateObject> children)

Adds the children of this StateObject to the given list.

Overrides:

addChildren in class AbstractStateObject

Parameters:

children - The list used to store the children

addNot

public NullComparisonExpressionStateObject addNot()

Makes sure the NOT identifier is specified.

Returns:

This object

getExpression

public NullComparisonExpression 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 AbstractStateObject

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)

getStateObject

public StateObject getStateObject()

Returns the StateObject representing the collection-valued path expression.

Returns:

The StateObject representing the collection-valued path expression

hasNot

public boolean hasNot()

Determines whether the NOT identifier is used or not.

Returns:

true if the NOT identifier is part of the expression; false otherwise

hasStateObject

public boolean hasStateObject()

Determines whether there is a StateObject representing the collection-valued path expression.

Returns:

true if the StateObject is not null; false otherwise

isEquivalent

public boolean isEquivalent(StateObject stateObject)

Determines whether the given StateObject is equivalent to this one, i.e. the information of both StateObject is the same.

Specified by:

isEquivalent in interface StateObject

Overrides:

isEquivalent in class AbstractStateObject

Parameters:

stateObject - The StateObject to compare its content to this one

Returns:

true if both object are equivalent; false otherwise

removeNot

public void removeNot()

Makes sure the NOT identifier is not specified.

setExpression

public void setExpression(NullComparisonExpression 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 the null expression

setNot

public void setNot(boolean not)

Sets whether the NOT identifier should be part of the expression or not.

Parameters:

not - true if the NOT identifier should be part of the expression; false otherwise

setStateObject

public void setStateObject(StateObject stateObject)

Sets the given StateObject as the collection-valued path expression.

Parameters:

stateObject - The StateObject that represents the collection-valued path expression

toggleNot

public void toggleNot()

Changes the visibility state of the NOT identifier.

toTextInternal

protected void toTextInternal(java.lang.Appendable writer)
                       throws java.io.IOException

Prints out a string representation of this StateObject, which should not be used to define a true string representation of a JPQL query but should be used for debugging purposes.

Specified by:

toTextInternal in class AbstractStateObject

Parameters:

writer - The writer used to print out the string representation

Throws:

java.io.IOException - This should never happens, it is only required because Appendable is used instead of any concrete class