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 * http://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, e.g. 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 /** Stores a reference to the associated configuration builder. */
39 private final CombinedConfigurationBuilder configurationBuilder;
40
41 /**
42 * Creates a new instance of {@code ConfigurationDeclaration} and initializes it.
43 *
44 * @param builder the associated configuration builder
45 * @param config the configuration this declaration is based onto
46 */
47 public ConfigurationDeclaration(final CombinedConfigurationBuilder builder, final HierarchicalConfiguration<?> config) {
48 super(config);
49 configurationBuilder = builder;
50 }
51
52 /**
53 * Gets the associated configuration builder.
54 *
55 * @return the configuration builder
56 */
57 public CombinedConfigurationBuilder getConfigurationBuilder() {
58 return configurationBuilder;
59 }
60
61 /**
62 * Gets the value of the {@code at} attribute.
63 *
64 * @return the value of the {@code at} attribute (can be <b>null</b>)
65 */
66 public String getAt() {
67 final String result = this.getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT_RES);
68 return result == null ? this.getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT) : result;
69 }
70
71 /**
72 * Gets a flag whether this is an optional configuration.
73 *
74 * @return a flag if this declaration points to an optional configuration
75 */
76 public boolean isOptional() {
77 Boolean value = this.getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL_RES, null);
78 if (value == null) {
79 value = this.getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL, Boolean.FALSE);
80 }
81 return value.booleanValue();
82 }
83
84 /**
85 * Gets a flag whether this configuration should always be created and added to the resulting combined configuration.
86 * This flag is evaluated only for optional configurations whose normal creation has caused an error. If for such a
87 * configuration the {@code forceCreate} attribute is set and the corresponding configuration provider supports this
88 * mode, an empty configuration will be created and added to the resulting combined configuration.
89 *
90 * @return the value of the {@code forceCreate} attribute
91 */
92 public boolean isForceCreate() {
93 return this.getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_FORCECREATE, false);
94 }
95
96 /**
97 * Returns a flag whether a builder with reloading support should be created. This may not be supported by all
98 * configuration builder providers.
99 *
100 * @return a flag whether a reloading builder should be created
101 */
102 public boolean isReload() {
103 return getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_RELOAD, false);
104 }
105
106 /**
107 * Gets the name for the represented configuration source. The name is optional, so this method can return
108 * <b>null</b>.
109 *
110 * @return the name of the associated configuration source or <b>null</b>
111 */
112 public String getName() {
113 return getConfiguration().getString(CombinedConfigurationBuilder.ATTR_NAME);
114 }
115
116 /**
117 * Gets the name of the bean factory. For configuration source declarations always a reserved factory is used. This
118 * factory's name is returned by this implementation.
119 *
120 * @return the name of the bean factory
121 */
122 @Override
123 public String getBeanFactoryName() {
124 return CombinedConfigurationBuilder.CONFIG_BEAN_FACTORY_NAME;
125 }
126
127 /**
128 * Gets the bean's class name. This implementation will always return <b>null</b>.
129 *
130 * @return the name of the bean's class
131 */
132 @Override
133 public String getBeanClassName() {
134 return null;
135 }
136
137 /**
138 * {@inheritDoc} This implementation checks for additional reserved attribute names. Note that in some cases the
139 * presence of other attribute names determine whether a name is reserved or not. For instance, per default the
140 * attribute {@code config-at} is reserved. However, if this attribute is not present, the attribute {@code at} is also
141 * considered as a reserved attribute. (This is mainly done for dealing with legacy configuration files supported by
142 * earlier versions of this library.)
143 */
144 @Override
145 protected boolean isReservedAttributeName(final String name) {
146 if (super.isReservedAttributeName(name)) {
147 return true;
148 }
149
150 final Set<String> attributes = getAttributeNames();
151 return CombinedConfigurationBuilder.ATTR_ATNAME.equals(name) && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_ATNAME)
152 || CombinedConfigurationBuilder.ATTR_OPTIONALNAME.equals(name)
153 && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_OPTIONALNAME);
154 }
155 }