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

All Implemented Interfaces:

StateObject
```
public class ExistsExpressionStateObject
extends AbstractSingleEncapsulatedExpressionStateObject
```
An EXISTS expression is a predicate that is true only if the result of the subquery consists of one or more values and that is false otherwise.
BNF: exists_expression ::= [NOT] EXISTS(subquery)

Since:

2.4

Version:

2.4

Author:

Pascal Filion

See Also:

ExistsExpression

Field Summary

Fields
Modifier and Type Field Description

static String NOT_PROPERTY
Notifies the visibility of the NOT identifier has changed.
- Fields inherited from class org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractSingleEncapsulatedExpressionStateObject
  STATE_OBJECT_PROPERTY

Constructor Summary

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

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`accept(StateObjectVisitor visitor)`	Visits this `StateObject` by the given `visitor`.
`ExistsExpressionStateObject`	`addNot()`	Makes sure the `NOT` identifier is specified.
`ExistsExpression`	`getExpression()`	Returns the actual parsed object if this `StateObject` representation of the JPQL query was created by parsing an existing JPQL query.
`String`	`getIdentifier()`	Returns the JPQL identifier of the expression represented by this `AbstractSingleEncapsulatedExpressionStateObject`.
`boolean`	`hasNot()`	Determines whether the `NOT` identifier is used or not.
`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(ExistsExpression 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)`
`void`	`toggleNot()`	Changes the visibility state of the `NOT` identifier.

Methods inherited from class org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractSingleEncapsulatedExpressionStateObject
getStateObject, hasStateObject, parse

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.
- Constructor Detail
  - ExistsExpressionStateObject
```
public ExistsExpressionStateObject(StateObject parent)
```
    Creates a new ExistsExpressionStateObject.
    
    Parameters:
    
    parent - The parent of this state object, which cannot be null
    
    Throws:
    
    NullPointerException - The given parent cannot be null
  - ExistsExpressionStateObject
```
public ExistsExpressionStateObject(StateObject parent,
                                   boolean not,
                                   StateObject stateObject)
```
    Creates a new ExistsExpressionStateObject.
    
    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 subquery
    
    Throws:
    
    NullPointerException - The given parent cannot be null
  - ExistsExpressionStateObject
```
public ExistsExpressionStateObject(StateObject parent,
                                   boolean not,
                                   String jpqlFragment)
```
    Creates a new ExistsExpressionStateObject.
    
    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
    
    jpqlFragment - The portion of the query representing the encapsulated expression
    
    Throws:
    
    NullPointerException - The given parent cannot be null
  - ExistsExpressionStateObject
```
public ExistsExpressionStateObject(StateObject parent,
                                   StateObject stateObject)
```
    Creates a new ExistsExpressionStateObject.
    
    Parameters:
    
    parent - The parent of this state object, which cannot be null
    
    stateObject - The StateObject representing the subquery
    
    Throws:
    
    NullPointerException - The given parent cannot be null
  - ExistsExpressionStateObject
```
public ExistsExpressionStateObject(StateObject parent,
                                   String jpqlFragment)
```
    Creates a new ExistsExpressionStateObject.
    
    Parameters:
    
    parent - The parent of this state object, which cannot be null
    
    jpqlFragment - The portion of the query representing the encapsulated expression
    
    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 ExistsExpressionStateObject addNot()
```
    Makes sure the NOT identifier is specified.
    
    Returns:
    
    This object
  - getExpression
```
public ExistsExpression 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 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
  - 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
  - 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 AbstractSingleEncapsulatedExpressionStateObject
    
    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(ExistsExpression 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 an EXISTS 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)
```
  - toggleNot
```
public void toggleNot()
```
    Changes the visibility state of the NOT identifier.

Class ExistsExpressionStateObject

Field Summary

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

Constructor Summary

Method Summary

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

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

Methods inherited from class java.lang.Object

Field Detail

NOT_PROPERTY

Constructor Detail

ExistsExpressionStateObject

ExistsExpressionStateObject

ExistsExpressionStateObject

ExistsExpressionStateObject

ExistsExpressionStateObject

Method Detail

accept

addNot

getExpression

getIdentifier

hasNot

isEquivalent

removeNot

setExpression

setNot

setStateObject

toggleNot