org.eclipse.persistence.jpa.jpql
Class DeclarationResolver

java.lang.Object
  org.eclipse.persistence.jpa.jpql.Resolver
      org.eclipse.persistence.jpa.jpql.DeclarationResolver

Direct Known Subclasses:

EclipseLinkDeclarationResolver

public class DeclarationResolver
extends Resolver

This Resolver is responsible to visit the current query (which is either the top-level query or a subquery) and gathers the information from the declaration clause. For a SELECT or DELETE clause, the information will be retrieved from the FROM clause. For an UDPATE clause, it will be retrieved from the unique identification range variable declaration.

Version:

2.4

Author:

Pascal Filion

Since:

2.3

Nested Class Summary

static class	DeclarationResolver.Declaration A Declaration represents either an identification variable declaration or a collection member declaration.
protected class	DeclarationResolver.DeclarationVisitor
protected class	DeclarationResolver.QualifyRangeDeclarationVisitor
protected class	DeclarationResolver.RootObjectExpressionVisitor This visitor takes care to support a subquery defined as a "root" object.

Constructor Summary

DeclarationResolver(DeclarationResolver parent, JPQLQueryContext queryContext)
Creates a new DeclarationResolver.

Method Summary

void	accept(ResolverVisitor visitor) Visits this Resolver by the given visitor.
protected void	addDeclaration(DeclarationResolver.Declaration declaration) Adds the given DeclarationResolver.Declaration at the end of the list.
void	addRangeVariableDeclaration(java.lang.String entityName, java.lang.String variableName) Registers a range variable declaration that will be used when a JPQL fragment is parsed.
protected DeclarationResolver.DeclarationVisitor	buildDeclarationVisitor()
protected DeclarationResolver.RootObjectExpressionVisitor	buildRootObjectExpressionVisitor()
protected IType	buildType() Resolves the IType of the property handled by this Resolver.
protected ITypeDeclaration	buildTypeDeclaration() Resolves the ITypeDeclaration of the property handled by this Resolver.
protected void	checkParent(Resolver parent)
void	convertUnqualifiedDeclaration(DeclarationResolver.Declaration declaration, java.lang.String outerVariableName) Converts the given DeclarationResolver.Declaration from being set as a range variable declaration to a path expression declaration.
void	dispose() Disposes the internal data.
java.util.List<DeclarationResolver.Declaration>	getDeclarations() Returns the ordered list of Declarations.
protected DeclarationResolver.DeclarationVisitor	getDeclarationVisitor()
java.util.Collection<Join>	getJoins(java.lang.String variableName) Returns the parsed representation of a JOIN and JOIN FETCH that were defined in the same declaration than the given range identification variable name.
protected java.util.Collection<Join>	getJoinsImp(java.lang.String variableName)
DeclarationResolver	getParent() Returns the parent of this Resolver.
protected IQuery	getQuery() Returns the external form representing the JPQL query.
protected JPQLQueryContext	getQueryContext() Returns the JPQLQueryContext that is used by this visitor.
Resolver	getResolver(java.lang.String variableName) Retrieves the Resolver mapped with the given identification variable.
protected Resolver	getResolverImp(java.lang.String variableName)
java.util.Set<java.lang.String>	getResultVariables() Returns the variables that got defined in the select expression.
java.util.Map<IdentificationVariable,java.lang.String>	getResultVariablesMap() Returns the map of result variables that got used to define a select expression.
protected DeclarationResolver.RootObjectExpressionVisitor	getRootObjectExpressionVisitor()
boolean	hasJoins() Determines whether the JPQL expression has JOIN expressions.
protected void	initialize(JPQLQueryContext queryContext) Initializes this DeclarationResolver.
boolean	isCollectionIdentificationVariable(java.lang.String variableName) Determines whether the given identification variable is defining a JOIN or IN expressions for a collection-valued field.
protected boolean	isCollectionIdentificationVariableImp(java.lang.String variableName)
boolean	isRangeIdentificationVariable(java.lang.String variableName) Determines whether the given variable name is an identification variable name used to define an abstract schema name.
protected boolean	isRangeIdentificationVariableImp(java.lang.String variableName)
boolean	isResultVariable(java.lang.String variable) Determines if the given variable is a result variable.
void	populate(Expression expression) Visits the current query (which is either the top-level query or a subquery) and gathers the information from the declaration clause.
protected DeclarationResolver.QualifyRangeDeclarationVisitor	qualifyRangeDeclarationVisitor()
protected Resolver	resolveRootObject(Expression expression) Resolves the "root" object represented by the given Expression.
protected java.lang.String	visitDeclaration(Expression expression, Expression identificationVariable)

Methods inherited from class org.eclipse.persistence.jpa.jpql.Resolver

addChild, getChild, getManagedType, getMapping, getParentManagedType, getParentMapping, getParentType, getParentTypeDeclaration, getProvider, getType, getType, getType, getTypeDeclaration, getTypeHelper, getTypeRepository, isNullAllowed, setNullAllowed

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DeclarationResolver

public DeclarationResolver(DeclarationResolver parent,
                           JPQLQueryContext queryContext)

Creates a new DeclarationResolver.

Parameters:

parent - The parent resolver if this is used for a subquery or null if it's used for the top-level query

queryContext - The context used to query information about the query

Method Detail

accept

public void accept(ResolverVisitor visitor)

Visits this Resolver by the given visitor.

Specified by:

accept in class Resolver

Parameters:

visitor - The visitor to visit this object

addDeclaration

protected final void addDeclaration(DeclarationResolver.Declaration declaration)

Adds the given DeclarationResolver.Declaration at the end of the list.

Parameters:

declaration - The DeclarationResolver.Declaration representing a single variable declaration

addRangeVariableDeclaration

public void addRangeVariableDeclaration(java.lang.String entityName,
                                        java.lang.String variableName)

Registers a range variable declaration that will be used when a JPQL fragment is parsed.

Parameters:

entityName - The name of the entity to be accessible with the given variable name

variableName - The identification variable used to navigate to the entity

buildDeclarationVisitor

protected DeclarationResolver.DeclarationVisitor buildDeclarationVisitor()

buildRootObjectExpressionVisitor

protected DeclarationResolver.RootObjectExpressionVisitor buildRootObjectExpressionVisitor()

buildType

protected IType buildType()

Resolves the IType of the property handled by this Resolver.

Overrides:

buildType in class Resolver

Returns:

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

buildTypeDeclaration

protected ITypeDeclaration buildTypeDeclaration()

Resolves the ITypeDeclaration of the property handled by this Resolver.

Specified by:

buildTypeDeclaration in class Resolver

Returns:

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

checkParent

protected void checkParent(Resolver parent)

Overrides:

checkParent in class Resolver

convertUnqualifiedDeclaration

public void convertUnqualifiedDeclaration(DeclarationResolver.Declaration declaration,
                                          java.lang.String outerVariableName)

Converts the given DeclarationResolver.Declaration from being set as a range variable declaration to a path expression declaration.

In this query "UPDATE Employee SET firstName = 'MODIFIED' WHERE (SELECT COUNT(m) FROM managedEmployees m) > 0" managedEmployees is an unqualified collection-valued path expression (employee.managedEmployees).

Parameters:

declaration - The DeclarationResolver.Declaration that was parsed to range over an abstract schema name but is actually ranging over a path expression

outerVariableName - The identification variable coming from the parent identification variable declaration

dispose

public void dispose()

Disposes the internal data.

getDeclarations

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

Returns the ordered list of Declarations.

Returns:

The Declarations of the current query that was parsed

getDeclarationVisitor

protected DeclarationResolver.DeclarationVisitor getDeclarationVisitor()

getJoins

public java.util.Collection<Join> getJoins(java.lang.String variableName)

Returns the parsed representation of a JOIN and 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 and JOIN FETCH expressions used in the same declaration or an empty collection if none was defined

getJoinsImp

protected java.util.Collection<Join> getJoinsImp(java.lang.String variableName)

getParent

public DeclarationResolver getParent()

Returns the parent of this Resolver.

Overrides:

getParent in class Resolver

Returns:

The parent of this Resolver

getQuery

protected IQuery getQuery()

Returns the external form representing the JPQL query.

Overrides:

getQuery in class Resolver

Returns:

The external form of the JPQL query

getQueryContext

protected JPQLQueryContext getQueryContext()

Returns the JPQLQueryContext that is used by this visitor.

Returns:

The JPQLQueryContext holding onto the JPQL query and the cached information

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

getResolverImp

protected Resolver getResolverImp(java.lang.String variableName)

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 or later.

Returns:

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

getResultVariablesMap

public java.util.Map<IdentificationVariable,java.lang.String> getResultVariablesMap()

Returns the map of result variables that got used to define a 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 map if none were defined

getRootObjectExpressionVisitor

protected DeclarationResolver.RootObjectExpressionVisitor getRootObjectExpressionVisitor()

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

initialize

protected void initialize(JPQLQueryContext queryContext)

Initializes this DeclarationResolver.

Parameters:

queryContext - The context used to query information about the query

isCollectionIdentificationVariable

public boolean isCollectionIdentificationVariable(java.lang.String variableName)

Determines whether the given identification variable is defining a JOIN or IN expressions for a collection-valued field.

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

isCollectionIdentificationVariableImp

protected boolean isCollectionIdentificationVariableImp(java.lang.String variableName)

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

isRangeIdentificationVariableImp

protected boolean isRangeIdentificationVariableImp(java.lang.String variableName)

isResultVariable

public boolean isResultVariable(java.lang.String variable)

Determines if the given variable is a result variable.

Parameters:

variable - The variable to check if it's a result variable

Returns:

true if the given variable is defined as a result variable; false otherwise

populate

public void populate(Expression expression)

Visits the current query (which is either the top-level query or a subquery) and gathers the information from the declaration clause.

Parameters:

expression - The Expression to visit in order to retrieve the information contained in the given query's declaration

qualifyRangeDeclarationVisitor

protected DeclarationResolver.QualifyRangeDeclarationVisitor qualifyRangeDeclarationVisitor()

resolveRootObject

protected Resolver resolveRootObject(Expression expression)

Resolves the "root" object represented by the given Expression. This will also handle using a subquery in the FROM clause. This is only support for EclipseLink.

Parameters:

expression -

Returns:

visitDeclaration

protected java.lang.String visitDeclaration(Expression expression,
                                            Expression identificationVariable)