001    /*
002     $Id: ListExpression.java,v 1.4 2005/02/01 10:46:54 russel 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)
040     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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.GroovyCodeVisitor;
053    import org.codehaus.groovy.classgen.AsmClassGenerator;
054    
055    /**
056     * Represents a list expression [1, 2, 3] which creates a mutable List
057     * 
058     * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
059     * @version $Revision: 1.4 $
060     */
061    public class ListExpression extends Expression {
062        private List expressions;
063    
064        public ListExpression() {
065            this(new ArrayList());
066        }
067        
068        public ListExpression(List expressions) {
069            this.expressions = expressions;
070            //
071        }
072        
073        public void addExpression(Expression expression) {
074            expressions.add(expression);
075        }
076        
077        public List getExpressions() {
078            return expressions;
079        }
080    
081        public void visit(GroovyCodeVisitor visitor) {
082            visitor.visitListExpression(this);
083        }
084    
085        public Expression transformExpression(ExpressionTransformer transformer) {
086            return new ListExpression(transformExpressions(getExpressions(), transformer));
087        }
088    
089        protected void resolveType(AsmClassGenerator resolver) {
090            for (int i = 0; i < expressions.size(); i++) {
091                Expression expression = (Expression) expressions.get(i);
092                expression.resolve(resolver);
093            }
094            super.setTypeClass(List.class);
095        }
096    
097        public Expression getExpression(int i) {
098            return (Expression) expressions.get(i);
099        }
100    
101        public String getText() {
102            StringBuffer buffer = new StringBuffer("[");
103            boolean first = true;
104            for (Iterator iter = expressions.iterator(); iter.hasNext(); ) {
105                if (first) {
106                    first = false;
107                }
108                else {
109                    buffer.append(", ");
110                }
111                
112                buffer.append(((Expression)iter.next()).getText());
113            }
114            buffer.append("]");
115            return buffer.toString();
116        }
117    
118        public String toString() {
119            return super.toString() + expressions;
120        }
121    
122        /**
123         * return the common element type of all the element
124         * @return
125         */
126        public Class getComponentTypeClass() {
127            boolean first = true;
128            Class cls = null;
129    
130            for (Iterator iter = expressions.iterator(); iter.hasNext(); ) {
131                Expression exp = (Expression) iter.next();
132                if (cls == null) {
133                    cls = exp.getTypeClass();
134                }
135                else {
136                    if (cls != exp.getTypeClass()) {
137                        // a heterogenous list
138                        return null;
139                    }
140                }
141            }
142            return cls;
143        }
144    
145    
146    }