/*******************************************************************************
 * Copyright (c) 2004, 2005 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

package org.eclipse.birt.report.model.api;

import org.eclipse.birt.report.model.api.metadata.IMetaDataDictionary;
import org.eclipse.birt.report.model.api.metadata.IMetaLogger;

import com.ibm.icu.util.ULocale;

/**
 * Represents the BIRT design engine as a whole. Used to create new sessions.
 * 
 * @see IMetaLogger
 */

public interface IDesignEngine
{

	/**
	 * Gets the meta-data of the design engine.
	 * 
	 * @return the meta-data of the design engine
	 */

	public IMetaDataDictionary getMetaData( );

	/**
	 * Creates a new design session handle. The application uses the handle to
	 * open, create and manage designs. The session also represents the user and
	 * maintains the user's locale information.
	 * 
	 * @param locale
	 *            the user's locale. If <code>null</code>, uses the system
	 *            locale.
	 * @param config
	 *            the platform config
	 * @return the design session handle
	 * @see SessionHandle
	 */

	public SessionHandle newSessionHandle( ULocale locale );

	/**
	 * Registers a <code>IMetaLogger</code> to record initialization errors.
	 * The logger will be notified of the errors during meta-data
	 * initialization. The meta-data system will be initialized once (and only
	 * once). Loggers should be registered before the first time a session is
	 * created so that it can be notified of the logging actions.
	 * 
	 * @param newLogger
	 *            the <code>MetaLogger</code> to be registered.
	 * 
	 * @see #removeMetaLogger(IMetaLogger)
	 */

	public void registerMetaLogger( IMetaLogger newLogger );

	/**
	 * Removes a <code>IMetaLogger</code>. This method will remove the logger
	 * from the list and close the logger if it has already been registered. The
	 * logger will no longer be notified of the errors during metadata
	 * initialization. Returns <code>true</code> if this logger manager
	 * contained the specified logger.
	 * 
	 * @param logger
	 *            the <code>MetaLogger</code> to be removed.
	 * @return <code>true</code> if this logger manager contained the
	 *         specified logger.
	 * 
	 * @see #registerMetaLogger(IMetaLogger)
	 */

	public boolean removeMetaLogger( IMetaLogger logger );
}
