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

Since:

2.4

Version:

2.4

Author:

Pascal Filion

See Also:

NullComparisonExpression

Field Summary

Fields
Modifier and Type	Field	Description
`static String`	`NOT_PROPERTY`	Notifies the visibility of the `NOT` identifier has changed.
`static String`	`STATE_OBJECT_PROPERTY`	Notifies the state object property has changed.

Constructor Summary

Constructors
Constructor	Description
`NullComparisonExpressionStateObject(StateObject parent)`	Creates a new `NullComparisonExpressionStateObject`.
`NullComparisonExpressionStateObject(StateObject parent, boolean not, String path)`	Creates a new `NullComparisonExpressionStateObject`.
`NullComparisonExpressionStateObject(StateObject parent, boolean not, StateObject stateObject)`	Creates a new `NullComparisonExpressionStateObject`.
`NullComparisonExpressionStateObject(StateObject parent, String path)`	Creates a new `NullComparisonExpressionStateObject`.
`NullComparisonExpressionStateObject(StateObject parent, StateObject stateObject)`	Creates a new `NullComparisonExpressionStateObject`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`accept(StateObjectVisitor visitor)`	Visits this `StateObject` by the given `visitor`.
`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.
`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.

Methods inherited from class org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractStateObject
addPropertyChangeListener, children, decorate, equals, findIdentificationVariable, getDeclaration, getDecorator, getGrammar, getManagedTypeProvider, getParent, getQueryBuilder, getRoot, getType, getType, getTypeHelper, getTypeRepository, hashCode, isDecorated, removePropertyChangeListener, setExpression, setParent, toString, toString, toText

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - NOT_PROPERTY
```
public static String NOT_PROPERTY
```
    Notifies the visibility of the NOT identifier has changed.
  - STATE_OBJECT_PROPERTY
```
public static final 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:
    
    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:
    
    NullPointerException - The given parent cannot be null
  - NullComparisonExpressionStateObject
```
public NullComparisonExpressionStateObject(StateObject parent,
                                           boolean not,
                                           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:
    
    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:
    
    NullPointerException - The given parent cannot be null
  - NullComparisonExpressionStateObject
```
public NullComparisonExpressionStateObject(StateObject parent,
                                           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:
    
    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
  - 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.

Class NullComparisonExpressionStateObject

Field Summary

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

NOT_PROPERTY

STATE_OBJECT_PROPERTY

Constructor Detail

NullComparisonExpressionStateObject

NullComparisonExpressionStateObject

NullComparisonExpressionStateObject

NullComparisonExpressionStateObject

NullComparisonExpressionStateObject

Method Detail

accept

addNot

getExpression

getStateObject

hasNot

hasStateObject

isEquivalent

removeNot

setExpression

setNot

setStateObject

toggleNot