/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2001 Sun
 * Microsystems, Inc. All Rights Reserved.
 */
package org.netbeans.api.mdr;

import org.openide.util.Lookup;
import javax.jmi.reflect.RefBaseObject;
import java.io.IOException;
import java.util.Collection;

/** JMI mapping utility. Generates JMI interfaces for a given metamodel.
 * Use {@link #getDefault} method to obtain the default instance.
 *
 * @author Martin Matula
 */
public abstract class JMIMapper {
    
    /** Generates JMI interfaces for the specified object
     * and the objects contained in it.
     * @param sf Implementation of {@link JMIStreamFactory} interface.
     * @param object Top-level object for interface generation. There are two possible kinds of objects that can be passed:
     * 

     *    
RefObject (instance) - interfaces for this instance together with interfaces for all transitively contained instances are generated.
     *    
RefPackage (package extent) - interfaces for all instances contained transitively in this package extent are generated.
     * 
     * @throws IOException I/O error during interfaces generation.
     */    
    public abstract void generate(JMIStreamFactory sf, RefBaseObject object) throws IOException;
    
    /** Returns the default JMI mapping utility in the system
     * @return default JMI mapping utility
     */
    public static synchronized JMIMapper getDefault() {
        // [PENDING] simple lookup should be used once the lookup is fixed (currently it does not preserve order)
        Lookup.Result result = Lookup.getDefault().lookup(
            new Lookup.Template(JMIMapper.class)
        );
        Collection instances = result.allInstances();
        return (instances.size() > 0 ? (JMIMapper) result.allInstances().iterator().next() : null);
    }
}