/*******************************************************************************
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html.
 * 
 * This file is a derivative of code released by the University of
 * California under the terms listed below.  
 *
 * Refinement Analysis Tools is Copyright (c) 2007 The Regents of the
 * University of California (Regents). Provided that this notice and
 * the following two paragraphs are included in any distribution of
 * Refinement Analysis Tools or its derivative work, Regents agrees
 * not to assert any of Regents' copyright rights in Refinement
 * Analysis Tools against recipient for recipient's reproduction,
 * preparation of derivative works, public display, public
 * performance, distribution or sublicensing of Refinement Analysis
 * Tools and derivative works, in source code and object code form.
 * This agreement not to assert does not confer, by implication,
 * estoppel, or otherwise any license or rights in any intellectual
 * property of Regents, including, but not limited to, any patents
 * of Regents or Regents' employees.
 * 
 * IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT,
 * INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
 * INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE
 * AND ITS DOCUMENTATION, EVEN IF REGENTS HAS BEEN ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *   
 * REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE AND FURTHER DISCLAIMS ANY STATUTORY
 * WARRANTY OF NON-INFRINGEMENT. THE SOFTWARE AND ACCOMPANYING
 * DOCUMENTATION, IF ANY, PROVIDED HEREUNDER IS PROVIDED "AS
 * IS". REGENTS HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT,
 * UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 */
package com.ibm.wala.demandpa.alg;

import com.ibm.wala.demandpa.alg.statemachine.StateMachine.State;

/**
 * Simple abstraction for pairing some type with a {@link State}.
 */
public abstract class WithState<T> {

  private final T wrapped;

  private final State state;

  private final int hc;
  
  public WithState(final T wrapped, final State state) {
    if (wrapped == null) {
      throw new IllegalArgumentException("null wrapped");
    }
    if (state == null) {
      throw new IllegalArgumentException("null state");
    }
    this.wrapped = wrapped;
    this.state = state;
    this.hc = 31 * state.hashCode() + wrapped.hashCode();
  }

  public State getState() {
    return state;
  }

  public T getWrapped() {
    return wrapped;
  }

  @Override
  public String toString() {
    return wrapped + ", STATE " + state;
  }

  @Override
  public int hashCode() {
    return hc;
  }

  @SuppressWarnings("unchecked")
  @Override
  public boolean equals(Object obj) {
    if (this == obj)
      return true;
    if (obj == null)
      return false;
    if (getClass() != obj.getClass())
      return false;
    final WithState<T> other = (WithState<T>) obj;
    if (state == null) {
      if (other.state != null)
        return false;
    } else if (!state.equals(other.state))
      return false;
    if (wrapped == null) {
      if (other.wrapped != null)
        return false;
    } else if (!wrapped.equals(other.wrapped))
      return false;
    return true;
  }
}