code: //==============================================================================
  //	
  //	Copyright (c) 2002-
  //	Authors:
  //	* Dave Parker <d.a.parker@cs.bham.ac.uk> (University of Birmingham/Oxford)
  //	
  //------------------------------------------------------------------------------
  //	
  //	This file is part of PRISM.
  //	
  //	PRISM is free software; you can redistribute it and/or modify
  //	it under the terms of the GNU General Public License as published by
  //	the Free Software Foundation; either version 2 of the License, or
  //	(at your option) any later version.
  //	
  //	PRISM 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 General Public License for more details.
  //	
  //	You should have received a copy of the GNU General Public License
  //	along with PRISM; if not, write to the Free Software Foundation,
  //	Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  //	
  //==============================================================================
  
  package parser.ast;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import prism.PrismUtils;
  
  /**
   * Class to represent coalition info, e.g., in an ExpressionStrategy object.
   * Stored as a list of strings which are either player names (e.g. "controller")
   * or player indices (e.g. "2"). Alternatively, "*" denotes all players.
   */
  public class Coalition
  {
  	/** Is coalition all players? (denoted by *) */
  	protected boolean allPlayers;
  	
  	/** Coalition: list of player names/indices */
  	protected List<String> players; 
  	
  	// Constructors
  
  	/**
  	 * Default constructor: empty player list
  	 */
  	public Coalition()
  	{
  		// Empty list of players
  		allPlayers = false;
  		players = new ArrayList<String>();
  	}
  
  	/**
  	 * Copy constructor
  	 */
  	public Coalition(Coalition c)
  	{
  		// Copy all info (though, strictly speaking, "players" is irrelevant if allPlayers==true
  		// (note that we access c.players directly since getPlayers() can return null)
  		allPlayers = c.isAllPlayers();
  		players = new ArrayList<String>(c.players);
  	}
  
  	// Set methods
  
  	/**
  	 * Make this coalition comprise all players (denoted "*")
  	 */
  	public void setAllPlayers()
  	{
  		allPlayers = true;
  		players.clear();;
  	}
  
  	/**
  	 * Make this coalition comprise these players
  	 * (each string can be a player name or an integer player index)
  	 */
  	public void setPlayers(List<String> players)
  	{
  		allPlayers = false;
  		this.players.clear();
  		this.players.addAll(players);
  	}
  
  	// Get methods
  
  	/**
  	 * Does this coalition comprise all players? (denoted "*")
  	 */
  	public boolean isAllPlayers()
  	{
  		return allPlayers;
  	}
  	
  	/**
  	 * Is this coalition empty?
  	 */
  	public boolean isEmpty()
  	{
  		return !allPlayers && players.isEmpty();
  	}
  	
  	/**
  	 * Get a list of strings describing the coalition
  	 * (each string can be a player name or an integer player index).
  	 * This will be null is the coalition is "*" (all players).
  	 */
  	public List<String> getPlayers()
  	{
  		return allPlayers ? null : players;
  	}
  	
  	/**
  	 * Check if a given player (specified by its index) is in the coalition,
  	 * i.e., if the index or the name of the player with this index is in the list.
  	 * The mapping from player indices to player names is passed in.
  	 */
  	public boolean isPlayerIndexInCoalition(int index, Map<Integer, String> playerNames)
  	{
  		if (allPlayers) {
  			return true;
  		}
  		if (players.contains("" + index)) {
  			return true;
  		}
  		String playerName = playerNames.get(index);
  		if (playerName != null && !"".equals(playerName) && players.contains(playerName)) {
  			return true;
  		}
  		return false;
  	}
  	
  	@Override
  	public String toString()
  	{
  		return allPlayers ? "*" : PrismUtils.joinString(players, ",");
  	}
  
  	@Override
  	public int hashCode()
  	{
  		final int prime = 31;
  		int result = 1;
  		result = prime * result + (allPlayers ? 1231 : 1237);
  		result = prime * result + ((players == null) ? 0 : players.hashCode());
  		return result;
  	}
  
  	@Override
  	public boolean equals(Object obj)
  	{
  		if (this == obj)
  			return true;
  		if (obj == null)
  			return false;
  		if (getClass() != obj.getClass())
  			return false;
  		Coalition other = (Coalition) obj;
  		if (allPlayers != other.allPlayers)
  			return false;
  		if (players == null) {
  			if (other.players != null)
  				return false;
  		} else if (!players.equals(other.players))
  			return false;
  		return true;
  	}
  }
  