1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://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.commons.configuration2.builder.combined;
18
19 import java.util.Set;
20
21 import org.apache.commons.configuration2.HierarchicalConfiguration;
22 import org.apache.commons.configuration2.beanutils.XMLBeanDeclaration;
23
24 /**
25 * <p>
26 * A specialized {@code BeanDeclaration} implementation that represents the declaration of a configuration source.
27 * </p>
28 * <p>
29 * Instances of this class are able to extract all information about a configuration source from the configuration
30 * definition file. The declaration of a configuration source is very similar to a bean declaration processed by
31 * {@code XMLBeanDeclaration}. There are very few differences, for example some reserved attributes like {@code optional} and
32 * {@code at}, and the fact that a bean factory is never needed.
33 * </p>
34 *
35 * @since 2.0
36 */
37 public class ConfigurationDeclaration extends XMLBeanDeclaration {
38
39 /** Stores a reference to the associated configuration builder. */
40 private final CombinedConfigurationBuilder configurationBuilder;
41
42 /**
43 * Creates a new instance of {@code ConfigurationDeclaration} and initializes it.
44 *
45 * @param builder the associated configuration builder
46 * @param config the configuration this declaration is based onto
47 */
48 public ConfigurationDeclaration(final CombinedConfigurationBuilder builder, final HierarchicalConfiguration<?> config) {
49 super(config);
50 configurationBuilder = builder;
51 }
52
53 /**
54 * Gets the value of the {@code at} attribute.
55 *
56 * @return the value of the {@code at} attribute (can be <strong>null</strong>)
57 */
58 public String getAt() {
59 final String result = getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT_RES);
60 return result == null ? getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT) : result;
61 }
62
63 /**
64 * Gets the bean's class name. This implementation will always return <strong>null</strong>.
65 *
66 * @return the name of the bean's class
67 */
68 @Override
69 public String getBeanClassName() {
70 return null;
71 }
72
73 /**
74 * Gets the name of the bean factory. For configuration source declarations always a reserved factory is used. This
75 * factory's name is returned by this implementation.
76 *
77 * @return the name of the bean factory
78 */
79 @Override
80 public String getBeanFactoryName() {
81 return CombinedConfigurationBuilder.CONFIG_BEAN_FACTORY_NAME;
82 }
83
84 /**
85 * Gets the associated configuration builder.
86 *
87 * @return the configuration builder
88 */
89 public CombinedConfigurationBuilder getConfigurationBuilder() {
90 return configurationBuilder;
91 }
92
93 /**
94 * Gets the name for the represented configuration source. The name is optional, so this method can return
95 * <strong>null</strong>.
96 *
97 * @return the name of the associated configuration source or <strong>null</strong>
98 */
99 public String getName() {
100 return getConfiguration().getString(CombinedConfigurationBuilder.ATTR_NAME);
101 }
102
103 /**
104 * Gets a flag whether this configuration should always be created and added to the resulting combined configuration.
105 * This flag is evaluated only for optional configurations whose normal creation has caused an error. If for such a
106 * configuration the {@code forceCreate} attribute is set and the corresponding configuration provider supports this
107 * mode, an empty configuration will be created and added to the resulting combined configuration.
108 *
109 * @return the value of the {@code forceCreate} attribute
110 */
111 public boolean isForceCreate() {
112 return getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_FORCECREATE, false);
113 }
114
115 /**
116 * Gets a flag whether this is an optional configuration.
117 *
118 * @return a flag if this declaration points to an optional configuration
119 */
120 public boolean isOptional() {
121 Boolean value = getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL_RES, null);
122 if (value == null) {
123 value = getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL, Boolean.FALSE);
124 }
125 return value.booleanValue();
126 }
127
128 /**
129 * Returns a flag whether a builder with reloading support should be created. This may not be supported by all
130 * configuration builder providers.
131 *
132 * @return a flag whether a reloading builder should be created
133 */
134 public boolean isReload() {
135 return getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_RELOAD, false);
136 }
137
138 /**
139 * {@inheritDoc} This implementation checks for additional reserved attribute names. Note that in some cases the
140 * presence of other attribute names determine whether a name is reserved or not. For instance, per default the
141 * attribute {@code config-at} is reserved. However, if this attribute is not present, the attribute {@code at} is also
142 * considered as a reserved attribute. (This is mainly done for dealing with legacy configuration files supported by
143 * earlier versions of this library.)
144 */
145 @Override
146 protected boolean isReservedAttributeName(final String name) {
147 if (super.isReservedAttributeName(name)) {
148 return true;
149 }
150
151 final Set<String> attributes = getAttributeNames();
152 return CombinedConfigurationBuilder.ATTR_ATNAME.equals(name) && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_ATNAME)
153 || CombinedConfigurationBuilder.ATTR_OPTIONALNAME.equals(name)
154 && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_OPTIONALNAME);
155 }
156 }