1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package javax.faces.view.facelets;
20
21 /**
22 * Foundation class for FaceletHandlers associated with markup in a Facelet document.
23 */
24 public abstract class TagHandler implements FaceletHandler
25 {
26 protected final String tagId;
27
28 protected final Tag tag;
29
30 protected final FaceletHandler nextHandler;
31
32 public TagHandler(TagConfig config)
33 {
34 this.tagId = config.getTagId();
35 this.tag = config.getTag();
36 this.nextHandler = config.getNextHandler();
37 }
38
39 /**
40 * Utility method for fetching the appropriate TagAttribute
41 *
42 * @param localName
43 * name of attribute
44 * @return TagAttribute if found, otherwise null
45 */
46 protected final TagAttribute getAttribute(String localName)
47 {
48 return this.tag.getAttributes().get(localName);
49 }
50
51 /**
52 * Utility method for fetching a required TagAttribute
53 *
54 * @param localName
55 * name of the attribute
56 * @return TagAttribute if found, otherwise error
57 * @throws TagException
58 * if the attribute was not found
59 */
60 protected final TagAttribute getRequiredAttribute(String localName) throws TagException
61 {
62 TagAttribute attr = this.getAttribute(localName);
63 if (attr == null)
64 {
65 throw new TagException(this.tag, "Attribute '" + localName + "' is required");
66 }
67
68 return attr;
69 }
70
71 /**
72 * {@inheritDoc}
73 */
74 @Override
75 public String toString()
76 {
77 return this.tag.toString();
78 }
79 }