/*
 * JBoss, Home of Professional Open Source.
 * See the COPYRIGHT.txt file distributed with this work for information
 * regarding copyright ownership.  Some portions may be licensed
 * to Red Hat, Inc. under one or more contributor license agreements.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301 USA.
 * Modified by
 * @author  Data Virtuality GmbH
 * @date    $Date$
 *  
 */

package org.teiid.net.socket;

import java.util.List;
import java.util.Properties;

import org.teiid.client.security.LogonResult;
import org.teiid.net.HostInfo;
import org.teiid.net.TeiidURL;



/**
 * Customizable ServerDiscovery interface
 */
public interface ServerDiscovery {
	
	/**
	 * Initialize the {@link ServerDiscovery}
	 * @param url
	 * @param p
	 */
	void init(TeiidURL url, Properties p);
	
	/**
	 * Get the currently known hosts.  Will be called prior to connecting and after
	 * authentication for each connection. 
	 * @param result, the current {@link LogonResult} - may be null if unauthenticated 
	 * @param instance, the currently connected instance - may be null if not connected
	 * @return
	 */
	List<HostInfo> getKnownHosts(LogonResult result, SocketServerInstance instance);
	
	/**
	 * Indicates that a connection was made successfully to the given host.
	 * @param info
	 */
	void connectionSuccessful(HostInfo info);
	
	/**
	 * Indicates that a connection could not be made to the given host.
	 * @param info
	 */
	void markInstanceAsBad(HostInfo info);
	
	/**
	 * Shutdown this {@link ServerDiscovery}
	 */
	void shutdown();
	
	/**
	 * Select the next instance to try.  The entry should be removed from the list
	 * when no more attempts are desired.  
	 * and not return null.
	 * @param hosts
	 * @return a non-null HostInfo to try
	 */
	HostInfo selectNextInstance(List<HostInfo> hosts);
		
}
