JavaToken.java

//  JavaToken.java

//  Class JavaToken
//  ------------------------------------------------------------------
/**
  *   Encapsulates information about a Java token.
  *
  *   @author   C. Vickery
  *   @version  1.0 - Spring, 2000
  */
  public class JavaToken                     implements JavaTokenTypes
  {
   
  //  Instance Information
  //  ================================================================
      private int     tokenType     = JTT_Undefined;
      private int     hashCode      = "".hashCode();
      private String  lexemeString  = null;

      private char    charValue     = '\u0000';
      private long    longValue     = 0;
      private double  doubleValue   = 0.0;
   
  //  Constructors
  //  ================================================================

  //  Generic constructor
  //  ----------------------------------------------------------------
    public JavaToken( int type, String lexeme )
    {
      //  Generic token initialization.
      tokenType     = type;
      lexemeString  = lexeme;
      hashCode      = lexeme.hashCode();
    }

  //  Constructors for char, long, and double literals.
  //  ----------------------------------------------------------------
    public JavaToken( int type, String lexeme, double d )
    {
      this( type, lexeme );
      doubleValue = d;
    }
    public JavaToken( int type, String lexeme, long l )
    {
      this( type, lexeme );
      longValue = l;
    }
    public JavaToken( int type, String lexeme, char c )
    {
      this( type, lexeme );
      charValue = c;
    }
   
    //  Accessor methods
    //  ==============================================================
      public int    getType()           { return tokenType;     }
      public int    hashCode()          { return hashCode;      }
      public String getLexemeString()   { return lexemeString;  }
      public char   getCharacterValue() { return charValue;     }
      public long   getLongValue()      { return longValue;     }
      public double getDoubleValue()    { return doubleValue;   }
   
    //  Override methods
    //  ==============================================================

    //  Method toString()
    //  --------------------------------------------------------------
    /**
      *   Overrides Object.toString() to provide a printable
      *   representation of information about this Java token.
      *
      *   @param  Void.
      *   @return Printable representation of information about this
      *           token.
      */
      public String toString()
      {
        String  returnValue;
        switch ( tokenType )
        {
          case JTT_Identifier:    returnValue = "Identifier:\t\t";
                                  break;
          case JTT_Keyword:       returnValue = "Keyword:\t\t";
                                  break;
          case JTT_String:        returnValue = "String literal:\t";
                                  break;
          case JTT_Character:     returnValue = "Character literal ("
                                                 + charValue + "):\t";
                                  break;
          case JTT_FixedPoint:    returnValue = "Long literal (" +
                                                 longValue + "):\t";
                                  break;
          case JTT_FloatingPoint: returnValue = "Double literal (" +
                                                 doubleValue + "):\t";
                                  break;
          case JTT_True:          returnValue = "True literal:\t\t";
                                  break;
          case JTT_False:         returnValue = "False literal:\t\t";
                                  break;
          case JTT_Null:          returnValue = "Null literal:\t\t";
                                  break;
          case JTT_Separator:     returnValue = "Separator:\t\t";
                                  break;
          case JTT_Operator:      returnValue = "Operator:\t\t";
                                  break;
          default:                returnValue =
                                            "Unknown token type:\t\t";
                                  break;
        }
        returnValue += lexemeString;
        if ( returnValue.length() > 56 )
        {
          returnValue = returnValue.substring( 0, 55 ) + " ...";
        }
        return returnValue;
      }

   }