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 org.apache.myfaces.custom.validatebeanbehavior;
20
21 import javax.faces.context.FacesContext;
22 import javax.validation.MessageInterpolator;
23 import javax.validation.ValidatorFactory;
24 import java.util.Locale;
25
26 /**
27 * Holder class to prevent NoClassDefFoundError in environments without Bean Validation.
28 * <p/>
29 * This is needed, because holder classes are loaded lazily. This means that when it's not
30 * used, it will not be loaded, parsed and initialized. The BeanValidator class is used always,
31 * so the MessageInterpolator references need to be in this separate class.
32 */
33 final class FacesMessageInterpolatorHolder {
34
35 // Needs to be volatile.
36 private static volatile FacesMessageInterpolator instance;
37
38 /**
39 * Helper method for initializing the FacesMessageInterpolator.
40 * <p/>
41 * It uses the "Single Check Idiom" as described in Joshua Bloch's Effective Java 2nd Edition.
42 *
43 * @param validatorFactory Used to obtain the MessageInterpolator.
44 * @return The instantiated MessageInterpolator for BeanValidator.
45 */
46 static MessageInterpolator get(final ValidatorFactory validatorFactory) {
47 FacesMessageInterpolatorHolder.FacesMessageInterpolator ret = instance;
48 if (ret == null) {
49 final MessageInterpolator interpolator = validatorFactory.getMessageInterpolator();
50 instance = ret = new FacesMessageInterpolator(interpolator);
51 }
52 return ret;
53 }
54
55 /**
56 * Standard MessageInterpolator, as described in the JSR-314 spec.
57 */
58 private static class FacesMessageInterpolator implements MessageInterpolator {
59 private final MessageInterpolator interpolator;
60
61 FacesMessageInterpolator(final MessageInterpolator interpolator) {
62 this.interpolator = interpolator;
63 }
64
65 public String interpolate(final String s, final Context context) {
66 final Locale locale = FacesContext.getCurrentInstance().getViewRoot().getLocale();
67 return interpolator.interpolate(s, context, locale);
68 }
69
70 public String interpolate(final String s, final Context context, final Locale locale) {
71 return interpolator.interpolate(s, context, locale);
72 }
73 }
74 }