1 /*
2 * Copyright 2002,2004 The Apache Software Foundation.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.apache.commons.jelly.tags.core;
17
18 import org.apache.commons.jelly.MissingAttributeException;
19 import org.apache.commons.jelly.TagSupport;
20 import org.apache.commons.jelly.XMLOutput;
21 import org.apache.commons.jelly.expression.Expression;
22
23 /***
24 * A tag which removes the variable of the given name from the current variable scope.
25 *
26 * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
27 * @version $Revision: 155420 $
28 */
29 public class RemoveTag extends TagSupport {
30
31 private Expression var;
32
33 public RemoveTag() {
34 }
35
36 // Tag interface
37 //-------------------------------------------------------------------------
38 public void doTag(XMLOutput output) throws MissingAttributeException {
39 if (var != null) {
40 context.removeVariable( var.evaluateAsString(context) );
41 }
42 else {
43 throw new MissingAttributeException("var");
44 }
45 }
46
47 // Properties
48 //-------------------------------------------------------------------------
49
50 /***
51 * Sets the name of the variable which will be removed by this tag..
52 */
53 public void setVar(Expression var) {
54 this.var = var;
55 }
56 }