bsh.BSHWhileStatement Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of aibench-shell Show documentation
The newest version!
/*
 * #%L
 * The AIBench Shell Plugin
 * %%
 * Copyright (C) 2006 - 2017 Daniel Glez-Peña and Florentino Fdez-Riverola
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 * 
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * .
 * #L%
 */
/*****************************************************************************
 *                                                                           *
 *  This file is part of the BeanShell Java Scripting distribution.          *
 *  Documentation and updates may be found at http://www.beanshell.org/      *
 *                                                                           *
 *  Sun Public License Notice:                                               *
 *                                                                           *
 *  The contents of this file are subject to the Sun Public License Version  *
 *  1.0 (the "License"); you may not use this file except in compliance with *
 *  the License. A copy of the License is available at http://www.sun.com    * 
 *                                                                           *
 *  The Original Code is BeanShell. The Initial Developer of the Original    *
 *  Code is Pat Niemeyer. Portions created by Pat Niemeyer are Copyright     *
 *  (C) 2000.  All Rights Reserved.                                          *
 *                                                                           *
 *  GNU Public License Notice:                                               *
 *                                                                           *
 *  Alternatively, the contents of this file may be used under the terms of  *
 *  the GNU Lesser General Public License (the "LGPL"), in which case the    *
 *  provisions of LGPL are applicable instead of those above. If you wish to *
 *  allow use of your version of this file only under the  terms of the LGPL *
 *  and not to allow others to use your version of this file under the SPL,  *
 *  indicate your decision by deleting the provisions above and replace      *
 *  them with the notice and other provisions required by the LGPL.  If you  *
 *  do not delete the provisions above, a recipient may use your version of  *
 *  this file under either the SPL or the LGPL.                              *
 *                                                                           *
 *  Patrick Niemeyer ([email protected])                                           *
 *  Author of Learning Java, O'Reilly & Associates                           *
 *  http://www.pat.net/~pat/                                                 *
 *                                                                           *
 *****************************************************************************/

package bsh;

/**
 * This class handles both while(){} statements and do{}while() statements.
 */
class BSHWhileStatement extends SimpleNode implements ParserConstants {
        public boolean isDoStatement;

        BSHWhileStatement(int id) {
                super(id);
        }

        public Object eval(CallStack callstack, Interpreter interpreter) throws EvalError {
                int numChild = jjtGetNumChildren();

                // Order of body and condition is swapped for do / while
                SimpleNode condExp, body = null;

                if (isDoStatement) {
                        condExp = (SimpleNode) jjtGetChild(1);
                        body = (SimpleNode) jjtGetChild(0);
                } else {
                        condExp = (SimpleNode) jjtGetChild(0);
                        if (numChild > 1) // has body, else just for side
                                // effects
                                body = (SimpleNode) jjtGetChild(1);
                }

                boolean doOnceFlag = isDoStatement;
                while (doOnceFlag || BSHIfStatement.evaluateCondition(condExp, callstack, interpreter)) {
                        if (body == null) // no body?
                                continue;

                        Object ret = body.eval(callstack, interpreter);

                        boolean breakout = false;
                        if (ret instanceof ReturnControl) {
                                switch (((ReturnControl) ret).kind) {
                                case RETURN:
                                        return ret;

                                case CONTINUE:
                                        continue;

                                case BREAK:
                                        breakout = true;
                                        break;
                                }
                        }
                        if (breakout)
                                break;

                        doOnceFlag = false;
                }

                return Primitive.VOID;
        }

}