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    1   /*
    2    $Id: GStringExpression.java,v 1.9 2004/07/10 03:31:37 bran Exp $
    3
    4    Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
    5
    6    Redistribution and use of this software and associated documentation
    7    ("Software"), with or without modification, are permitted provided
    8    that the following conditions are met:
    9
    10   1. Redistributions of source code must retain copyright
    11      statements and notices.  Redistributions must also contain a
    12      copy of this document.
    13
    14   2. Redistributions in binary form must reproduce the
    15      above copyright notice, this list of conditions and the
    16      following disclaimer in the documentation and/or other
    17      materials provided with the distribution.
    18
    19   3. The name "groovy" must not be used to endorse or promote
    20      products derived from this Software without prior written
    21      permission of The Codehaus.  For written permission,
    22      please contact info@codehaus.org.
    23
    24   4. Products derived from this Software may not be called "groovy"
    25      nor may "groovy" appear in their names without prior written
    26      permission of The Codehaus. "groovy" is a registered
    27      trademark of The Codehaus.
    28
    29   5. Due credit should be given to The Codehaus -
    30      http://groovy.codehaus.org/
    31
    32   THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
    33   ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
    34   NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
    35   FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
    36   THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
    37   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    38   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    39   SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    40   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    41   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    42   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
    43   OF THE POSSIBILITY OF SUCH DAMAGE.
    44
    45   */
    46  package org.codehaus.groovy.ast.expr;
    47
    48  import groovy.lang.GString;
    49
    50  import java.util.ArrayList;
    51  import java.util.Iterator;
    52  import java.util.List;
    53
    54  import org.codehaus.groovy.ast.GroovyCodeVisitor;
    55  import org.codehaus.groovy.classgen.AsmClassGenerator2;
    56
    57  /***
    58   * Represents a String expression which contains embedded values inside
    59   * it such as "hello there ${user} how are you" which is expanded lazily
    60   *
    61   * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
    62   * @version $Revision: 1.9 $
    63   */
    64  public class GStringExpression extends Expression {
    65
    66      private String verbatimText;
    67      private List strings = new ArrayList();
    68      private List values = new ArrayList();
    69
    70      public GStringExpression(String verbatimText) {
    71          this.verbatimText = verbatimText;
    72          super.setTypeClass(GString.class);
    73      }
    74
    75      public GStringExpression(String verbatimText, List strings, List values) {
    76          this.verbatimText = verbatimText;
    77          this.strings = strings;
    78          this.values = values;
    79          super.setTypeClass(GString.class);
    80      }
    81
    82      public void visit(GroovyCodeVisitor visitor) {
    83          visitor.visitGStringExpression(this);
    84      }
    85
    86      public Expression transformExpression(ExpressionTransformer transformer) {
    87          return new GStringExpression(
    88              verbatimText,
    89              transformExpressions(strings, transformer),
    90              transformExpressions(values, transformer));
    91      }
    92
    93      protected void resolveType(AsmClassGenerator2 resolver) {
    94          //
    95      }
    96
    97      public String toString() {
    98          return super.toString() + "[strings: " + strings + " values: " + values + "]";
    99      }
    100
    101     public List getStrings() {
    102         return strings;
    103     }
    104
    105     public List getValues() {
    106         return values;
    107     }
    108
    109     public void addString(ConstantExpression text) {
    110         if (text == null) {
    111             throw new NullPointerException("Cannot add a null text expression");
    112         }
    113         strings.add(text);
    114     }
    115
    116     public void addValue(Expression value) {
    117         // If the first thing is an value, then we need a dummy empty string in front of it so that when we
    118         // toString it they come out in the correct order.
    119         if (strings.size() == 0)
    120             strings.add(ConstantExpression.EMPTY_STRING);
    121         values.add(value);
    122     }
    123
    124     public Expression getValue(int idx) {
    125         return (Expression) values.get(idx);
    126     }
    127
    128     public boolean isConstantString() {
    129         return values.isEmpty();
    130     }
    131
    132     public Expression asConstantString() {
    133         StringBuffer buffer = new StringBuffer();
    134         for (Iterator iter = strings.iterator(); iter.hasNext();) {
    135             ConstantExpression expression = (ConstantExpression) iter.next();
    136             Object value = expression.getValue();
    137             if (value != null) {
    138                 buffer.append(value);
    139             }
    140         }
    141         return new ConstantExpression(buffer.toString());
    142     }
    143 }