certificate.java

来自「Java版的SAT求解器」· Java 代码 · 共 79 行

/*
 * Certificate.java	2.0 05/04/19
 *
 * Copyright 2004-2005 Positronic Software.
 *
 *
 */
 /**
 * A class which represents a certificate. A certificate is a mapping of a set
 * of BooleanVariables into {true,false}. A certificate is used to represent a
 * solution of a satisfiability problem.
 *
 * @author  Kerry Michael Soileau
 * <blockquote><pre>
 * [e-mail]
 * http://web.wt.net/~ksoileau/index.htm
 * </pre></blockquote>
 * @version 2.0, 05/04/19
 * @see ICertificate
 * @see HashMap
 * @see IBooleanVariable
 * @see Iterator
 * @see BooleanLiteralException
 * @see List
 */

package positronic.satisfiability.elements;

import positronic.satisfiability.exceptions.BooleanLiteralException;
import positronic.util.ArrayListSet;

public class Certificate implements ICertificate
{
  private ArrayListSet booleanLiterals;

  public void add(IBooleanVariable x, boolean val) throws BooleanLiteralException
  {
  	this.getBooleanLiterals().add(BooleanLiteral.getBooleanLiteral(x,!val));
  }

  public boolean containsBooleanVariable(IBooleanVariable x) throws BooleanLiteralException
  {
    if(!(x instanceof IBooleanVariable))
      return false;
    return this.getBooleanLiterals().contains(x);
  }

  public ArrayListSet getBooleanLiterals() throws BooleanLiteralException
  {
  	if(this.booleanLiterals==null)
  		this.booleanLiterals=new ArrayListSet();
    return this.booleanLiterals;
  }

  public boolean getValue(IBooleanVariable x) throws BooleanLiteralException
  {
    if(!this.containsBooleanVariable(x))
      return false; //default if IBooleanVariable x is not in Certificate
    int ind=this.getBooleanLiterals().indexOf(x);
    return !((IBooleanLiteral)this.getBooleanLiterals().get(ind)).isBarred();
  }

  public void setBooleanLiterals(ArrayListSet booleanLiterals)
  {
    this.booleanLiterals = booleanLiterals;
  }

  public String toString()
  {
    try
    {
      return this.getBooleanLiterals().toString();
    }
    catch(BooleanLiteralException err)
    {
      return null;
    }
  }
}