import Token;

/**
 * Tokens that take parameters, such as identifiers and numbers.
 * Make sure to create these tokens with
 *   ParameterizedToken.build(String)
 * rather than
 *   new ParameterizedToken(...)
 *
 * @author Samuel A. Rebelsky
 * @version 1.0 of February 2001.
 */
public class ParameterizedToken
  extends Token
{
  // +--------+--------------------------------------------------
  // | Fields |
  // +--------+

  /** The value associated with the token. */
  protected String value;

  // +--------------+--------------------------------------------
  // | Constructors |
  // +--------------+
 
  /** 
   * Create a new parameterized token with a particular value.
   */ 
  public ParameterizedToken(String val) {
    this.value = val;
  } // ParameterizedToken(String)

  // +----------------+------------------------------------------
  // | Static Methods |
  // +----------------+

  /**
   * Build a new token.
   */
  public static Token build(String val) {
    return new ParameterizedToken(val);
  } // build(String)

  // +---------+-------------------------------------------------
  // | Methods |
  // +---------+

  /** 
   * Convert to a string for easy printing.
   */
  public String toString() {
    return "PARAMETERIZED(" + this.value + ")";
  } // toString()
  
  /**
   * Determine if this token equals another object.  That
   * only happens if both are ParameterizedTokens and they
   * have the same value.
   *
   * Warning!  Subclasses should probably override this method.
   * Otherwise, two different tokens with the same parameter
   * will be treated as equal.
   */
  public boolean equals(Object other) {
    return ( (other instanceof ParameterizedToken) 
             && (this.equals((ParameterizedToken) other)) );
  } // equals(Object)
 
  /**
   * Determine if this token equals another parameterized token.
   * That only happens if they have the same associated value.
   *
   * While subclasses may not need to override this method, they
   * may want to provide a more restricted version.
   */
  public boolean equals(ParameterizedToken other) {
    return this.value.equals(other.value);
  } // equals(ParameterizedToken)

} // class ParameterizedToken