Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
ClientIdBinding |
|
| 1.75;1.75 |
1 | // Copyright 2006 The Apache Software Foundation | |
2 | // | |
3 | // Licensed under the Apache License, Version 2.0 (the "License"); | |
4 | // you may not use this file except in compliance with the License. | |
5 | // You may obtain a copy of the License at | |
6 | // | |
7 | // http://www.apache.org/licenses/LICENSE-2.0 | |
8 | // | |
9 | // Unless required by applicable law or agreed to in writing, software | |
10 | // distributed under the License is distributed on an "AS IS" BASIS, | |
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
12 | // See the License for the specific language governing permissions and | |
13 | // limitations under the License. | |
14 | ||
15 | package org.apache.tapestry.binding; | |
16 | ||
17 | import org.apache.hivemind.ApplicationRuntimeException; | |
18 | import org.apache.hivemind.Location; | |
19 | import org.apache.hivemind.util.Defense; | |
20 | import org.apache.tapestry.IBinding; | |
21 | import org.apache.tapestry.IComponent; | |
22 | import org.apache.tapestry.coerce.ValueConverter; | |
23 | ||
24 | /** | |
25 | * An implementation of Tapestry {@link IBinding} that simplifies | |
26 | * access to a component's clientId.<br/> | |
27 | * You can use this binding in order to safely find out the | |
28 | * client-side id that was (or will be) generated for a given | |
29 | * component. | |
30 | * | |
31 | * <p/> | |
32 | * Here's an example of how to get the client id of a Tapestry component: | |
33 | * <code> | |
34 | * <span jwcid="@Any" dojoType="myDojoComponent" contentId="clientId:content" /> | |
35 | * </code> | |
36 | * <p/> | |
37 | * The previous code can also be written using the ognl binding: | |
38 | * <code> | |
39 | * <span jwcid="@Any" dojoType="myDojoComponent" contentId="ognl:components.content.clientId" /> | |
40 | * </code> | |
41 | * but the clientId binding is more compact and performs much faster. | |
42 | */ | |
43 | public class ClientIdBinding extends AbstractBinding | |
44 | { | |
45 | private final IComponent _component; | |
46 | ||
47 | private final String _componentId; | |
48 | ||
49 | public ClientIdBinding(String description, ValueConverter valueConverter, Location location, | |
50 | IComponent component, String componentId) | |
51 | { | |
52 | 0 | super(description, valueConverter, location); |
53 | ||
54 | 0 | Defense.notNull(component, "component"); |
55 | 0 | Defense.notNull(componentId, "componentId"); |
56 | ||
57 | 0 | _component = component; |
58 | 0 | _componentId = componentId; |
59 | 0 | } |
60 | ||
61 | public Object getObject() | |
62 | { | |
63 | try | |
64 | { | |
65 | 0 | return _component.getComponent(_componentId).getClientId(); |
66 | } | |
67 | 0 | catch (Exception ex) |
68 | { | |
69 | 0 | throw new ApplicationRuntimeException(ex.getMessage(), getLocation(), ex); |
70 | } | |
71 | } | |
72 | ||
73 | public Object getComponent() | |
74 | { | |
75 | 0 | return _component; |
76 | } | |
77 | ||
78 | public boolean isInvariant() | |
79 | { | |
80 | // clientId can change even for the same component, so ... | |
81 | 0 | return false; |
82 | } | |
83 | ||
84 | } |