package de.fhdw.wtf.persistence.meta;
   
   /**
    * Represents the specialization-relationship between an ancestor and its descendant.
    */
   public class Specialization {
   	
   	/**
   	 * The ancestor of this specialization-relationship.
  	 */
  	private final Type ancestor;
  	/**
  	 * The descendant of this specialization-relationship.
  	 */
  	private final Type descendant;
  	
  	/**
  	 * Instantiates a new specialization-object with ancestor and descendant.
  	 * 
  	 * @param ancestor
  	 *            the ancestor of this specialization-relationship.
  	 * @param descendant
  	 *            the descendant of this specialization-relationship.
  	 */
  	public Specialization(final Type ancestor, final Type descendant) {
  		this.ancestor = ancestor;
  		this.descendant = descendant;
  	}
  	
  	/**
  	 * @return the ancestor of this specialization-relationship.
  	 */
  	public Type getAncestor() {
  		return this.ancestor;
  	}
  	
  	/**
  	 * @return the descendant of this specialization-relationship.
  	 */
  	public Type getDescendant() {
  		return this.descendant;
  	}
  	
  	@Override
  	public boolean equals(final java.lang.Object obj) {
  		if (obj instanceof Specialization) {
  			final Specialization objAsSpecialization = (Specialization) obj;
  			return objAsSpecialization.getAncestor().isTheSameAs(this.getAncestor())
  					&& objAsSpecialization.getDescendant().isTheSameAs(this.getDescendant());
  		}
  		return false;
  	}
  	
  	/**
  	 * Constant 1 for calculating hashCode.
  	 */
  	private static final int HASHCODE_PRIME_FACTOR_1 = 13;
  	/**
  	 * Constant 2 for calculating hashCode.
  	 */
  	private static final int HASHCODE_PRIME_FACTOR_2 = 27;
  	/**
  	 * Constant 2 for calculating hashCode.
  	 */
  	private static final int HASHCODE_PRIME_FACTOR_3 = 42;
  	
  	@Override
  	public int hashCode() {
  		int code = HASHCODE_PRIME_FACTOR_3;
  		
  		code += HASHCODE_PRIME_FACTOR_1 * this.getAncestor().hashCode();
  		code += HASHCODE_PRIME_FACTOR_2 * this.getDescendant().hashCode();
  		
  		return code;
  	}
  	
  }