001    /*
002     $Id: Expression.java,v 1.6 2005/11/13 16:42:09 blackdrag Exp $
003    
004     Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005    
006     Redistribution and use of this software and associated documentation
007     ("Software"), with or without modification, are permitted provided
008     that the following conditions are met:
009    
010     1. Redistributions of source code must retain copyright
011        statements and notices.  Redistributions must also contain a
012        copy of this document.
013    
014     2. Redistributions in binary form must reproduce the
015        above copyright notice, this list of conditions and the
016        following disclaimer in the documentation and/or other
017        materials provided with the distribution.
018    
019     3. The name "groovy" must not be used to endorse or promote
020        products derived from this Software without prior written
021        permission of The Codehaus.  For written permission,
022        please contact info@codehaus.org.
023    
024     4. Products derived from this Software may not be called "groovy"
025        nor may "groovy" appear in their names without prior written
026        permission of The Codehaus. "groovy" is a registered
027        trademark of The Codehaus.
028    
029     5. Due credit should be given to The Codehaus -
030        http://groovy.codehaus.org/
031    
032     THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033     ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
036     THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037     INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039     SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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041     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043     OF THE POSSIBILITY OF SUCH DAMAGE.
044    
045     */
046    package org.codehaus.groovy.ast.expr;
047    
048    import java.util.ArrayList;
049    import java.util.Iterator;
050    import java.util.List;
051    
052    import org.codehaus.groovy.ast.ASTNode;
053    import org.codehaus.groovy.ast.ClassHelper;
054    import org.codehaus.groovy.ast.ClassNode;
055    
056    /**
057     * Represents a base class for expressions which evaluate as an object
058     * 
059     * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
060     * @version $Revision: 1.6 $
061     */
062    public abstract class Expression extends ASTNode {
063    
064        private ClassNode type=ClassHelper.DYNAMIC_TYPE;
065        
066        /**
067         * Return a copy of the expression calling the transformer on any nested expressions 
068         * @param transformer
069         * @return
070         */
071        public abstract Expression transformExpression(ExpressionTransformer transformer);
072    
073        /**
074         * Transforms the list of expressions
075         * @return a new list of transformed expressions
076         */
077        protected List transformExpressions(List expressions, ExpressionTransformer transformer) {
078            List list = new ArrayList(expressions.size());
079            for (Iterator iter = expressions.iterator(); iter.hasNext(); ) {
080                list.add(transformer.transform((Expression) iter.next()));
081            }
082            return list;
083        }
084        
085        public ClassNode getType() {
086            return type;
087        }
088        
089        public void setType(ClassNode t) {
090            type=t;
091        }
092    }