Source Code Cross Referenced for ParameterSelector.java in  » Content-Management-System » apache-lenya-2.0 » org » apache » cocoon » selection » Java Source Code / Java DocumentationJava Source Code and Java Documentation

01:        /*
02:         * Licensed to the Apache Software Foundation (ASF) under one or more
03:         * contributor license agreements.  See the NOTICE file distributed with
04:         * this work for additional information regarding copyright ownership.
05:         * The ASF licenses this file to You under the Apache License, Version 2.0
06:         * (the "License"); you may not use this file except in compliance with
07:         * the License.  You may obtain a copy of the License at
08:         * 
09:         *      http://www.apache.org/licenses/LICENSE-2.0
10:         * 
11:         * Unless required by applicable law or agreed to in writing, software
12:         * distributed under the License is distributed on an "AS IS" BASIS,
13:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14:         * See the License for the specific language governing permissions and
15:         * limitations under the License.
16:         */
17:        package org.apache.cocoon.selection;
18:
19:        import org.apache.avalon.framework.parameters.Parameters;
20:        import org.apache.avalon.framework.thread.ThreadSafe;
21:
22:        import java.util.Map;
23:
24:        /**
25:         * A <code>Selector</code> that matches a string in the parameters object passed to it.
26:         *
27:         * <pre>
28:         *  &lt;map:selector name="parameter" factory="org.apache.cocoon.selection.ParameterSelector"/&gt;
29:         *
30:         *   &lt;map:select type="parameter"&gt;
31:         *      &lt;map:parameter name="parameter-selector-test" value="{mySitemapParameter}"/&gt;
32:         *
33:         *      &lt;map:when test="myParameterValue"&gt;
34:         *         &lt;!-- executes iff {mySitemapParameter} == "myParameterValue" --&gt;
35:         *         &lt;map:transform src="stylesheets/page/uk.xsl"/&gt;
36:         *      &lt;/map:when&gt;
37:         *      &lt;map:otherwise&gt;
38:         *         &lt;map:transform src="stylesheets/page/us.xsl"/&gt;
39:         *      &lt;/map:otherwise&gt;
40:         *   &lt;/map:select&gt;
41:         * </pre>
42:         *
43:         * The purpose of this selector is to allow an action to set parameters
44:         * and to be able to select between different pipeline configurations
45:         * depending on those parameters.
46:         *
47:         * @author <a href="mailto:leo.sutic@inspireinfrastructure.com">Leo Sutic</a>
48:         * @author <a href="mailto:sylvain@apache.org">Sylvain Wallez</a>
49:         * @version CVS $Id: ParameterSelector.java 433543 2006-08-22 06:22:54Z crossley $
50:         */
51:        public class ParameterSelector implements  ThreadSafe, Selector {
52:
53:            public boolean select(String expression, Map objectModel,
54:                    Parameters parameters) {
55:                String compareToString = parameters.getParameter(
56:                        "parameter-selector-test", null);
57:                return compareToString != null
58:                        && compareToString.equals(expression);
59:            }
60:        }