org.eclipse.persistence.jpa.internal.jpql

Class JPQLQueryContext

java.lang.Object

org.eclipse.persistence.jpa.internal.jpql.JPQLQueryContext

public class JPQLQueryContext
extends java.lang.Object

This context is used to store information related to the JPQL query.

Since:

2.3

Version:

2.3.1

Author:

Pascal Filion

Constructor Summary

Constructors

Constructor and Description
JPQLQueryContext() Creates a new JPQLQueryContext.

Method Summary

Methods

Modifier and Type	Method and Description
void	dispose() Disposes the internal data.
void	disposeSubqueryContext() Disposes this context, which is the current context being used for a subquery.
DeclarationResolver	getActualDeclarationResolver() Returns the DeclarationResolver of this context and not from the current query's declaration.
Expression	getCurrentQuery() Returns the current Expression being manipulated, which is either the top-level query or a subquery.
java.util.List<DeclarationResolver.Declaration>	getDeclarations() Returns the ordered list of Declarations.
IType	getEnumType(java.lang.String enumTypeName) Returns the IType representing the possible given enum type.
java.util.Collection<JoinFetch>	getJoinFetches(java.lang.String variableName) Returns the parsed representation of a JOIN FETCH that were defined in the same declaration than the given range identification variable name.
JPQLExpression	getJPQLExpression() Returns the parsed tree representation of the JPQL query.
java.lang.String	getJPQLQuery() Returns the string representation of the JPQL query.
IMapping	getMapping(Expression expression) Returns the IMapping for the field represented by the given Expession.
IType	getParameterType(InputParameter inputParameter) Retrieves, if it can be determined, the type of the given InputParameter.
JPQLQueryContext	getParent() Returns the parent context if the current context is not the root context.
IManagedTypeProvider	getProvider() Retrieves the provider of managed types.
IQuery	getQuery() Returns the external form of the JPQL query.
Resolver	getResolver(Expression expression) Creates or retrieved the cached Resolver for the given Expression.
Resolver	getResolver(java.lang.String variableName) Retrieves the Resolver mapped with the given identification variable.
java.util.Set<java.lang.String>	getResultVariables() Returns the variables that got defined in the select expression.
IType	getType(java.lang.Class<?> type) Retrieves the external type for the given Java type.
IType	getType(Expression expression) Returns the IType of the given Expression.
IType	getType(java.lang.String typeName) Retrieves the external class for the given fully qualified class name.
ITypeDeclaration	getTypeDeclaration(Expression expression) Returns the ITypeDeclaration of the field handled by this Resolver.
TypeHelper	getTypeHelper() Returns a helper that gives access to the most common types.
ITypeRepository	getTypeRepository() Returns the type repository for the application.
boolean	hasJoins() Determines whether the JPQL expression has JOIN expressions.
boolean	isCollectionVariableName(java.lang.String variableName) Determines whether the given identification variable is defining a join or a collection member declaration expressions.
boolean	isRangeIdentificationVariable(java.lang.String variableName) Determines whether the given variable name is an identification variable name used to define an abstract schema name.
java.lang.String	literal(Expression expression, LiteralType type) Retrieves the "literal" from the given Expression.
void	newSubqueryContext(Expression currentQuery) Changes the state of this context to use the given subquery.
void	setJPQLExpression(JPQLExpression jpqlExpression) Sets the parsed tree representation of the JPQL query.
void	setQuery(IQuery query) Sets the external form of the JPQL query, which will be parsed and information will be extracted for later access.
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

JPQLQueryContext

public JPQLQueryContext()

Creates a new JPQLQueryContext.

Method Detail

dispose

public void dispose()

Disposes the internal data.

disposeSubqueryContext

public void disposeSubqueryContext()

Disposes this context, which is the current context being used for a subquery. Once it's disposed, any information retrieved will be for the subquery's parent query.

getActualDeclarationResolver

public DeclarationResolver getActualDeclarationResolver()

Returns the DeclarationResolver of this context and not from the current query's declaration.

Returns:

The DeclarationResolver for this context

getCurrentQuery

public Expression getCurrentQuery()

Returns the current Expression being manipulated, which is either the top-level query or a subquery.

Returns:

Either the top-level query or a subquery

getDeclarations

public java.util.List<DeclarationResolver.Declaration> getDeclarations()

Returns the ordered list of Declarations.

Returns:

The Declarations of the current query that was parsed

getEnumType

public IType getEnumType(java.lang.String enumTypeName)

Returns the IType representing the possible given enum type. If the type name

Parameters:

enumTypeName - The fully qualified enum type with the constant

Returns:

The external form for the given Enum type

getJoinFetches

public java.util.Collection<JoinFetch> getJoinFetches(java.lang.String variableName)

Returns the parsed representation of a JOIN FETCH that were defined in the same declaration than the given range identification variable name.

Parameters:

variableName - The name of the identification variable that should be used to define an abstract schema name

Returns:

The JOIN FETCH expressions used in the same declaration or an empty collection if none was defined

getJPQLExpression

public JPQLExpression getJPQLExpression()

Returns the parsed tree representation of the JPQL query.

Returns:

The parsed tree representation of the JPQL query

getJPQLQuery

public java.lang.String getJPQLQuery()

Returns the string representation of the JPQL query.

Returns:

The string representation of the JPQL query

getMapping

public IMapping getMapping(Expression expression)

Returns the IMapping for the field represented by the given Expession.

Parameters:

expression - The Expression representing a state field path expression or a collection-valued path expression

Returns:

Either the IMapping or null if none exists

getParameterType

public IType getParameterType(InputParameter inputParameter)

Retrieves, if it can be determined, the type of the given InputParameter. The type will be guessed based on its location within expression.

Note: Both named and positional input parameter can be used.

Parameters:

inputParameter - The InputParameter to retrieve its type

Returns:

Either the closest type of the input parameter or null if the type could not be determined

getParent

public JPQLQueryContext getParent()

Returns the parent context if the current context is not the root context.

Returns:

The parent context or null if the current context is the root

getProvider

public IManagedTypeProvider getProvider()

Retrieves the provider of managed types.

Returns:

The object that has access to the application's managed types.

getQuery

public IQuery getQuery()

Returns the external form of the JPQL query.

Returns:

The external form of the JPQL query

getResolver

public Resolver getResolver(Expression expression)

Creates or retrieved the cached Resolver for the given Expression. The Resolver can return the IType and ITypeDeclaration of the Expression and either the IManagedType or the IMapping.

Parameters:

expression - The Expression for which its Resolver will be retrieved

Returns:

Resolver for the given Expression

getResolver

public Resolver getResolver(java.lang.String variableName)

Retrieves the Resolver mapped with the given identification variable. If the identification is not defined in the declaration traversed by this resolver, than the search will traverse the parent hierarchy.

Parameters:

variableName - The identification variable that maps a Resolver

Returns:

The Resolver mapped with the given identification variable

getResultVariables

public java.util.Set<java.lang.String> getResultVariables()

Returns the variables that got defined in the select expression. This only applies to JPQL queries built for JPA 2.0.

Returns:

The variables identifying the select expressions, if any was defined or an empty set if none were defined

getType

public IType getType(java.lang.Class<?> type)

Retrieves the external type for the given Java type.

Parameters:

type - The Java type to wrap with an external form

Returns:

The external form of the given type

getType

public IType getType(Expression expression)

Returns the IType of the given Expression.

Parameters:

expression - The Expression for which its type will be calculated

Returns:

Either the IType that was resolved by this Resolver or the IType for IType.UNRESOLVABLE_TYPE if it could not be resolved

getType

public IType getType(java.lang.String typeName)

Retrieves the external class for the given fully qualified class name.

Parameters:

name - The fully qualified class name of the class to retrieve

Returns:

The external form of the class to retrieve

getTypeDeclaration

public ITypeDeclaration getTypeDeclaration(Expression expression)

Returns the ITypeDeclaration of the field handled by this Resolver.

Parameters:

expression - The Expression for which its type declaration will be calculated

Returns:

Either the ITypeDeclaration that was resolved by this Resolver or the ITypeDeclaration for IType.UNRESOLVABLE_TYPE if it could not be resolved

getTypeHelper

public TypeHelper getTypeHelper()

Returns a helper that gives access to the most common types.

Returns:

A helper containing a collection of methods related to IType

getTypeRepository

public ITypeRepository getTypeRepository()

Returns the type repository for the application.

Returns:

The repository of ITypes

hasJoins

public boolean hasJoins()

Determines whether the JPQL expression has JOIN expressions.

Returns:

true if the query or subquery being traversed contains JOIN expressions; false otherwise

isCollectionVariableName

public boolean isCollectionVariableName(java.lang.String variableName)

Determines whether the given identification variable is defining a join or a collection member declaration expressions.

Parameters:

variableName - The identification variable to check for what it maps

Returns:

true if the given identification variable maps a collection-valued field defined in a JOIN or IN expression; false if it's not defined or it's mapping an abstract schema name

isRangeIdentificationVariable

public boolean isRangeIdentificationVariable(java.lang.String variableName)

Determines whether the given variable name is an identification variable name used to define an abstract schema name.

Parameters:

variableName - The name of the variable to verify if it's defined in a range variable declaration in the current query or any parent query

Returns:

true if the variable name is mapping an abstract schema name; false if it's defined in a collection member declaration

literal

public java.lang.String literal(Expression expression,
                       LiteralType type)

Retrieves the "literal" from the given Expression. The literal to retrieve depends on the given type. The literal is basically a string value like an identification variable name, an input parameter, a path expression, an abstract schema name, etc.

Parameters:

expression - The Expression to visit

type - The LiteralType helps to determine what to retrieve from the visited Expression

Returns:

A value from the given Expression or an empty string if the given Expression and the LiteralType do not match

newSubqueryContext

public void newSubqueryContext(Expression currentQuery)

Changes the state of this context to use the given subquery.

Parameters:

currentQuery - The parsed tree representation of the subquery that will become the current query

See Also:

#disposeSubQueryContext()

setJPQLExpression

public void setJPQLExpression(JPQLExpression jpqlExpression)

Sets the parsed tree representation of the JPQL query. If the expression was parsed outside of the scope of this context, then this method has to be invoked before setQuery(IQuery) because the JPQL query is automatically parsed by that method.

Parameters:

jpqlExpression - The parsed representation of the JPQL query to manipulate

See Also:

setQuery(IQuery)

setQuery

public void setQuery(IQuery query)

Sets the external form of the JPQL query, which will be parsed and information will be extracted for later access.

Parameters:

query - The external form of the JPQL query

See Also:

setJPQLExpression(JPQLExpression)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object