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 * A base tag for wiring state to an object instance based on rules populated at the time of creating a MetaRuleset.
23 */
24 public abstract class MetaTagHandler extends TagHandler
25 {
26 private Class _lastType = Object.class;
27
28 private Metadata _mapper;
29
30 public MetaTagHandler(TagConfig config)
31 {
32 super(config);
33 }
34
35 /**
36 * Extend this method in order to add your own rules.
37 *
38 * @param type
39 * @return
40 *
41 * FIXME: EG _ GENERIC
42 */
43 protected abstract MetaRuleset createMetaRuleset(Class type);
44
45 /**
46 * Invoking/extending this method will cause the results of the created MetaRuleset to auto-wire state to
47 * the passed instance.
48 *
49 * @param ctx
50 * @param instance
51 */
52 protected void setAttributes(FaceletContext ctx, Object instance)
53 {
54 if (instance != null)
55 {
56 Class<?> type = instance.getClass();
57 if (_mapper == null || !_lastType.equals(type))
58 {
59 _lastType = type;
60 _mapper = createMetaRuleset(type).finish();
61 }
62
63 _mapper.applyMetadata(ctx, instance);
64 }
65 }
66 }