| /* |
| * Copyright (c) 2006, 2021 Oracle and/or its affiliates. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v. 2.0 which is available at |
| * http://www.eclipse.org/legal/epl-2.0, |
| * or the Eclipse Distribution License v. 1.0 which is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause |
| */ |
| |
| // Contributors: |
| // Oracle - initial API and implementation |
| // |
| package org.eclipse.persistence.jpa.jpql.tools.resolver; |
| |
| import org.eclipse.persistence.jpa.jpql.tools.spi.IManagedType; |
| import org.eclipse.persistence.jpa.jpql.tools.spi.IMapping; |
| import org.eclipse.persistence.jpa.jpql.tools.spi.ITypeDeclaration; |
| |
| /** |
| * This {@link Resolver} is responsible to resolve a single path of a path expression (state field |
| * path expression, singled valued object field, or a collection-valued path expression). |
| * |
| * @see CollectionValuedFieldResolver |
| * @see StateFieldResolver |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public abstract class AbstractPathResolver extends Resolver { |
| |
| /** |
| * The {@link IManagedType} representing this single valued object field path. |
| */ |
| private IManagedType managedType; |
| |
| /** |
| * This flag is used to prevent resolving the {@link IManagedType} more than once and no managed |
| * type could be found the first time. |
| */ |
| private boolean managedTypeResolved; |
| |
| /** |
| * The mapping of the last path of the path expression or <code>null</code> if it could not be found. |
| */ |
| private IMapping mapping; |
| |
| /** |
| * This flag is used to prevent resolving the {@link IMapping} more than once and no mapping |
| * could be found the first time. |
| */ |
| private boolean mappingResolved; |
| |
| /** |
| * The name of the path for which its type will be retrieved. |
| */ |
| protected final String path; |
| |
| /** |
| * Creates a new <code>AbstractPathResolver</code>. |
| * |
| * @param parent The parent {@link Resolver}, which is never <code>null</code> |
| * @param path The name of the path |
| */ |
| protected AbstractPathResolver(Resolver parent, String path) { |
| super(parent); |
| this.path = path; |
| parent.addChild(path, this); |
| } |
| |
| @Override |
| protected ITypeDeclaration buildTypeDeclaration() { |
| IMapping mapping = getMapping(); |
| if (mapping != null) { |
| return mapping.getTypeDeclaration(); |
| } |
| return getTypeHelper().unknownTypeDeclaration(); |
| } |
| |
| @Override |
| public IManagedType getManagedType() { |
| |
| if ((managedType == null) && !managedTypeResolved) { |
| managedTypeResolved = true; |
| |
| IMapping mapping = getMapping(); |
| |
| if (mapping != null) { |
| managedType = resolveManagedType(mapping); |
| } |
| } |
| |
| return managedType; |
| } |
| |
| @Override |
| public final IMapping getMapping() { |
| if ((mapping == null) && !mappingResolved) { |
| mapping = resolveMapping(); |
| mappingResolved = true; |
| } |
| return mapping; |
| } |
| |
| /** |
| * Returns the single path represented by this {@link Resolver}. |
| * |
| * @return The single path represented by this {@link Resolver} |
| */ |
| public final String getPath() { |
| return path; |
| } |
| |
| /** |
| * Resolves this path's {@link IManagedType} by using the given {@link IMapping}. |
| * |
| * @param mapping The {@link IMapping}, which is never <code>null</code>, is used to calculate |
| * the {@link IManagedType} |
| * @return The {@link IManagedType} for the given {@link IMapping}, if it has one; <code>null</code> |
| * if the type is a primitive |
| */ |
| protected abstract IManagedType resolveManagedType(IMapping mapping); |
| |
| /** |
| * Retrieves the {@link IMapping} for the given property name. |
| * |
| * @return Either the {@link IMapping} or <code>null</code> if none exists |
| */ |
| protected IMapping resolveMapping() { |
| IManagedType managedType = getParentManagedType(); |
| if (managedType != null) { |
| return managedType.getMappingNamed(path); |
| } |
| return null; |
| } |
| |
| @Override |
| public String toString() { |
| return path; |
| } |
| } |