org.eclipse.persistence.jpa.jpql.KeyResolver Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation

EclipseLink build based upon Git transaction 346465e

There is a newer version: 5.0.0-B07

/*******************************************************************************
 * Copyright (c) 2006, 2013 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 v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation
 *
 ******************************************************************************/
package org.eclipse.persistence.jpa.jpql;

import org.eclipse.persistence.jpa.jpql.spi.IManagedType;
import org.eclipse.persistence.jpa.jpql.spi.IType;
import org.eclipse.persistence.jpa.jpql.spi.ITypeDeclaration;

/**
 * This {@link Resolver} is responsible to return the map key, which means that for identification
 * variables referring to an instance of an association or collection represented as a {@link
 * java.util.Map Map}, the identification variable is of the abstract schema type of the map key.
 *
 * @see ValueResolver
 *
 * @version 2.4.1
 * @since 2.3
 * @author Pascal Filion
 */
@SuppressWarnings("nls")
public class KeyResolver extends Resolver {

	/**
	 * Creates a new KeyResolver.
	 *
	 * @param parent The parent {@link Resolver}, which is never null
	 */
	public KeyResolver(Resolver parent) {
		super(parent);
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void accept(ResolverVisitor visitor) {
		visitor.visit(this);
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected IType buildType() {

		ITypeDeclaration typeDeclaration = getTypeDeclaration();

		if (getTypeHelper().isMapType(typeDeclaration.getType())) {
			ITypeDeclaration[] typeParameters = typeDeclaration.getTypeParameters();

			if (typeParameters.length > 0) {
				return typeParameters[0].getType();
			}
		}

		return getTypeHelper().objectType();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected ITypeDeclaration buildTypeDeclaration() {
		return getParentTypeDeclaration();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public IManagedType getManagedType() {
		return getProvider().getManagedType(getType());
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public String toString() {
		return "KEY(" + getParent() + ")";
	}
}