/*******************************************************************************
 * 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.tools.spi;

import org.eclipse.persistence.jpa.jpql.tools.TypeHelper;

/**
 * The external representation of the repository of Java types, which gives access to the
 * application's classes.
 * <p>
 * <b>Important</b>: {@link IType#UNRESOLVABLE_TYPE} has to be handled by the implementer, which
 * has to be done in {@link #getType(String)}. It indicates the type is unresolvable or simply
 * unknown.
 * <p>
 * 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.
 *
 * @version 2.3
 * @since 2.3
 * @author Pascal Filion
 */
public interface ITypeRepository extends IExternalForm {

	/**
	 * Returns the {@link IType} representing the possible given enum constant. If the given value
	 * does not represent an enum constant, then <code>null</code> is returned.
	 *
	 * @param enumTypeName The fully qualified enum type with the constant
	 * @return The external form for the given Enum type or <code>null</code> if none exists
	 */
	IType getEnumType(String enumTypeName);

	/**
	 * Retrieves the external type for the given Java type.
	 *
	 * @param type The Java type to wrap with an external form
	 * @return The external form of the given type
	 */
	IType getType(Class<?> type);

	/**
	 * Retrieves the external class for the given fully qualified class name.
	 *
	 * @param typeName The fully qualified class name of the class to retrieve
	 * @return The external form of the class to retrieve
	 */
	IType getType(String typeName);

	/**
	 * Returns a helper that gives access to the most common {@link IType types}.
	 *
	 * @return A helper containing a collection of methods related to {@link IType}
	 */
	TypeHelper getTypeHelper();
}