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.Collection;
20 import java.util.HashMap;
21 import java.util.LinkedList;
22 import java.util.Map;
23 import java.util.stream.Stream;
24
25 import org.apache.commons.beanutils.DynaBean;
26 import org.apache.commons.beanutils.DynaClass;
27 import org.apache.commons.beanutils.DynaProperty;
28
29 /**
30 * <p>
31 * An implementation of {@code DynaClass} which combines the properties of multiple other {@code DynaClass} instances.
32 * </p>
33 *
34 * @since 2.0
35 */
36 final class MultiWrapDynaClass implements DynaClass {
37
38 /** An empty array for converting the properties collection to an array. */
39 private static final DynaProperty[] EMPTY_PROPS = {};
40
41 /** A collection with all properties of this class. */
42 private final Collection<DynaProperty> properties;
43
44 /** A map for accessing properties by name. */
45 private final Map<String, DynaProperty> namedProperties;
46
47 /**
48 * Creates a new instance of {@code MultiWrapDynaClass} and initializes it with the collection of classes to be wrapped.
49 *
50 * @param wrappedCls the collection with wrapped classes
51 */
52 public MultiWrapDynaClass(final Collection<? extends DynaClass> wrappedCls) {
53 properties = new LinkedList<>();
54 namedProperties = new HashMap<>();
55 initProperties(wrappedCls);
56 }
57
58 @Override
59 public DynaProperty[] getDynaProperties() {
60 return properties.toArray(EMPTY_PROPS);
61 }
62
63 @Override
64 public DynaProperty getDynaProperty(final String name) {
65 return namedProperties.get(name);
66 }
67
68 /**
69 * {@inheritDoc} The name of this class is not relevant.
70 */
71 @Override
72 public String getName() {
73 return null;
74 }
75
76 /**
77 * Initializes the members related to the properties of the wrapped classes.
78 *
79 * @param wrappedCls the collection with the wrapped classes
80 */
81 private void initProperties(final Collection<? extends DynaClass> wrappedCls) {
82 wrappedCls.forEach(cls -> Stream.of(cls.getDynaProperties()).forEach(p -> {
83 properties.add(p);
84 namedProperties.put(p.getName(), p);
85 }));
86 }
87
88 /**
89 * {@inheritDoc} This implementation always throws an exception because it is not possible to instantiate a bean of
90 * multiple classes.
91 */
92 @Override
93 public DynaBean newInstance() throws IllegalAccessException, InstantiationException {
94 throw new UnsupportedOperationException("Cannot create an instance of MultiWrapDynaBean.");
95 }
96 }