/**
  * Copyright (c): Uwe Schmidt, FH Wedel
  *
  * You may study, modify and distribute this source code
  * FOR NON-COMMERCIAL PURPOSES ONLY.
  * This copyright message has to remain unchanged.
  *
  * Note that this document is provided 'as is',
  * WITHOUT WARRANTY of any kind either expressed or implied.
  */

public
class BinaryPlus extends BinaryExpr {

  public
  BinaryPlus(Expr left, Expr right) {
    super(left, right);
  }

  // Implemetierung der Schablonenmethoden

  protected
  Object op2(Object v1, Object v2) {

    // + fuer int
    if ( v1 instanceof Integer
	 &&
	 v2 instanceof Integer ) {

      return
	new Integer( ((Integer)v1).intValue()
		     +
		     ((Integer)v2).intValue() );
    }

    // + fuer double
    if ( v1 instanceof Double
	 &&
	 v2 instanceof Double ) {

      return
	new Double( ((Double)v1).doubleValue()
		    +
		    ((Double)v2).doubleValue() );
    }

    // nicht erlaubtes Argument
    throw
      new IllegalArgumentException("binary + : illegal operand types");
  }

  //--------------------

  protected
  String op2ToString() {
    return
      "+";
  }
}