termnumber.java

来自「SHOP2 一个人工智能里面关于任务分解和任务规划的系统。JSHOP2是其jav」· Java 代码 · 共 88 行

package JSHOP2;

/** Each numerical term both at compile time and at run time, is an instance
 *  of this class.
 *
 *  @author Okhtay Ilghami
 *  @author <a href="http://www.cs.umd.edu/~okhtay">http://www.cs.umd.edu/~okhtay</a>
 *  @version 1.0.3
*/
public class TermNumber extends Term
{
  /** The value of the numerical term.
  */
  private double number;

  /** To initialize this numerical term.
   *
   *  @param numberIn
   *          the value this numerical term is set to have.
  */
  public TermNumber(double numberIn)
  {
    number = numberIn;
  }

  /** Since this term is a numerical term, binding will not change it,
   *  therefore, simply this numerical term itself is returned.
  */
  public Term bind(Term[] binding)
  {
    return this;
  }

  /** Whether or not another term is equivalent to this numerical term.
  */
  public boolean equals(Term t)
  {
    //-- 't' is not a numerical term.
    if (!(t instanceof TermNumber))
      return false;

    //-- Check if 't' has the same numerical value.
    return (number == ((TermNumber)t).number);
  }

  /** Find a unifier between this numerical term and another given term. Since
   *  this term is a number, this boils down to whether or not the other given
   *  term is equal to this one.
  */
  public boolean findUnifier(Term t, Term[] binding)
  {
    return ((t instanceof TermVariable) || equals(t));
  }

  /** To get the value of this numerical term.
   *
   *  @return
   *          the value of this numerical term.
  */
  public double getNumber()
  {
    return number;
  }

  /** This function always returns <code>true</code> because a numerical term
   *  is always ground by definition.
  */
  public boolean isGround()
  {
    return true;
  }

  /** This function produces Java code to create this numerical.
  */
  public String toCode()
  {
    return "new TermNumber(" + number + ")";
  }

  /** This function returns the <code>String</code> representation of the value
   *  of this numerical term.
  */
  public String toString()
  {
    return String.valueOf(number);
  }
}