1 /* 2 * Copyright (c) 2001, Zoltan Farkas All Rights Reserved. 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * This library is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 */ 18 19 package net.sf.zel.instr; 20 21 import net.sf.zel.nr.Operable; 22 import net.sf.zel.vm.*; 23 24 25 public final class MUL extends Instruction 26 { 27 private static final long serialVersionUID = -872688683600090372L; 28 29 private MUL(){}; 30 31 /** 32 * if any of the operands are null the result is null 33 * 34 * @param context 35 * @throws ZExecutionException 36 */ 37 38 public void execute(ExecutionContext context) throws ZExecutionException 39 { 40 final Operable val1 = (Operable) context.popSyncStackVal(); 41 final Operable val2 = (Operable) context.popSyncStackVal(); 42 if (val1 != null && val2 != null) 43 context.stack.push(val1.multiply(val2)); 44 else 45 context.stack.push(null); 46 47 context.ip++; 48 } 49 /** 50 * instance 51 */ 52 public static final Instruction instance = new MUL(); 53 }