package edu.neu.ccs.evergreen.exception;

import edu.neu.ccs.evergreen.model.Constraint;
import edu.neu.ccs.evergreen.model.State;

/**
 * Exception used to signal a contradiction.
 */
@SuppressWarnings("serial")
public class ContradictionException extends RuntimeException {

	private State state;

	private Constraint constraint;

	/**
	 * Create a new exception.
	 * 
	 * @param message
	 *            Reason for contradiction
	 */
	public ContradictionException(String message) {
		this(message, null, null);
	}

	/**
	 * Create a new exception.
	 * 
	 * @param message
	 *            Reason for contradiction
	 * @param constraint
	 *            Constraint that caused the contradiction
	 */
	public ContradictionException(String message, Constraint constraint) {
		this(message, null, constraint);
	}

	/**
	 * Create a new exception.
	 * 
	 * @param message
	 *            Reason for contradiction
	 * @param state
	 *            State at the time of the contradiction
	 * @param constraint
	 *            Constraint that caused the contradiction
	 */
	public ContradictionException(String message, State state,
			Constraint constraint) {
		super(message);
		this.state = state;
		this.constraint = constraint;
	}

	/**
	 * State active when contradiction occurred.
	 * 
	 * @return State
	 */
	public State getState() {
		return state;
	}

	/**
	 * Constraint involved in contradiction.
	 * 
	 * @return Constraint
	 */
	public Constraint getConstraint() {
		return constraint;
	}
}