org.eclipse.persistence.jpa.jpql

Class Resolver

java.lang.Object

org.eclipse.persistence.jpa.jpql.Resolver

Direct Known Subclasses:

AbsFunctionResolver, AbstractPathResolver, ClassNameResolver, ClassResolver, CollectionEquivalentResolver, DeclarationResolver, EntityResolver, EnumLiteralResolver, FromSubqueryResolver, IdentificationVariableResolver, KeyResolver, NullResolver, NumericResolver, SubqueryEntityResolver, SumFunctionResolver, TreatResolver, ValueResolver

public abstract class Resolver
extends java.lang.Object

A Resolver is responsible to resolve a property by retrieving either the managed type, the mapping, the type and the type declaration depending on the type of resolver.

Provisional API: This interface is part of an interim API that is still under development and expected to change significantly before reaching stability. It is available at this early stage to solicit feedback from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken (repeatedly) as the API evolves.

Since:

2.3

Version:

2.4

Author:

Pascal Filion

Method Summary

Modifier and Type	Method and Description
abstract void	accept(ResolverVisitor visitor) Visits this Resolver by the given visitor.
IManagedType	getManagedType() Returns the IManagedType associated with the field handled by this Resolver.
IMapping	getMapping() Returns the IMapping for the wrapped field.
Resolver	getParent() Returns the parent of this Resolver.
IType	getType() Returns the IType of the field handled by this Resolver.
boolean	isNullAllowed() Determines whether the Expression to be created, which wraps the attribute or query key name allows the target of the 1:1 relationship to be null if there is no corresponding relationship in the database.
void	setNullAllowed(boolean nullAllowed) Sets whether the Expression to be created, which wraps the attribute or query key name allows the target of the 1:1 relationship to be null if there is no corresponding relationship in the database.

Methods inherited from class java.lang.Object

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

Method Detail

accept

public abstract void accept(ResolverVisitor visitor)

Visits this Resolver by the given visitor.

Parameters:

visitor - The visitor to visit this object

getManagedType

public IManagedType getManagedType()

Returns the IManagedType associated with the field handled by this Resolver. If this Resolver does not handle a field that has a IManagedType, then null should be returned.

For example: "SELECT e FROM Employee e", the Resolver for e would be returning the IManagedType for Employee.

Returns:

Either the IManagedType, if it could be resolved; null otherwise

getMapping

public IMapping getMapping()

Returns the IMapping for the wrapped field.

Returns:

Either the IMapping or null if none exists

getParent

public Resolver getParent()

Returns the parent of this Resolver.

Returns:

The parent of this Resolver

getType

public final IType getType()

Returns the IType of the field handled by this Resolver.

Returns:

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

isNullAllowed

public boolean isNullAllowed()

Determines whether the Expression to be created, which wraps the attribute or query key name allows the target of the 1:1 relationship to be null if there is no corresponding relationship in the database.

Returns:

true to allow null if the corresponding relationship in the database does not exists; false otherwise

setNullAllowed

public void setNullAllowed(boolean nullAllowed)

Sets whether the Expression to be created, which wraps the attribute or query key name allows the target of the 1:1 relationship to be null if there is no corresponding relationship in the database.

Parameters:

nullAllowed - true to allow null if the corresponding relationship in the database does not exists; false otherwise