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

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.AggregateFunctionStateObject
                  org.eclipse.persistence.jpa.jpql.model.query.CountFunctionStateObject

All Implemented Interfaces:

StateObject

public class CountFunctionStateObject
extends AggregateFunctionStateObject

One of the aggregate functions. The return type of this function is a Long.

BNF: expression ::= COUNT ([DISTINCT] identification_variable | state_field_path_expression | single_valued_object_path_expression)

Version:

2.4

See Also:

CountFunction

Author:

Pascal Filion

Since:

2.4

Field Summary

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

DISTINCT_PROPERTY

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

STATE_OBJECT_PROPERTY

Constructor Summary

CountFunctionStateObject(StateObject parent)
Creates a new CountFunctionStateObject.

CountFunctionStateObject(StateObject parent, boolean distinct, StateObject stateObject)
Creates a new CountFunctionStateObject.

CountFunctionStateObject(StateObject parent, boolean distinct, java.lang.String path)
Creates a new CountFunctionStateObject.

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

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

Method Summary

void	accept(StateObjectVisitor visitor) Visits this StateObject by the given visitor.
CountFunction	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(CountFunction 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.

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

hasDistinct, isEquivalent, setDistinct, setStateObject, toggleDistinct, toTextEncapsulatedExpression

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

addChildren, getStateObject, hasStateObject, parse

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

CountFunctionStateObject

public CountFunctionStateObject(StateObject parent)

Creates a new CountFunctionStateObject.

Parameters:

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

Throws:

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

CountFunctionStateObject

public CountFunctionStateObject(StateObject parent,
                                boolean distinct,
                                StateObject stateObject)

Creates a new CountFunctionStateObject.

Parameters:

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

distinct - true to add DISTINCT to the query in order to have distinct values; false if it is not required

stateObject - The StateObject representing the encapsulated expression

Throws:

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

CountFunctionStateObject

public CountFunctionStateObject(StateObject parent,
                                boolean distinct,
                                java.lang.String path)

Creates a new CountFunctionStateObject.

Parameters:

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

distinct - true to add DISTINCT to the query in order to have distinct values; false if it is not required

path - Either the identification variable or the state field path expression

Throws:

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

CountFunctionStateObject

public CountFunctionStateObject(StateObject parent,
                                StateObject stateObject)

Creates a new CountFunctionStateObject.

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

CountFunctionStateObject

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

Creates a new CountFunctionStateObject.

Parameters:

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

path - Either the identification variable or the state field path expression

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 CountFunction 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 AggregateFunctionStateObject

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(CountFunction 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 COUNT expression