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
18 package org.apache.shardingsphere.infra.rule.attribute;
19
20 import java.util.Arrays;
21 import java.util.Collection;
22 import java.util.Optional;
23
24 /**
25 * Rule attribute.
26 */
27 public final class RuleAttributes {
28
29 private final Collection<RuleAttribute> attributes;
30
31 public RuleAttributes(final RuleAttribute... attributes) {
32 this.attributes = Arrays.asList(attributes);
33 }
34
35 /**
36 * Find rule attribute.
37 *
38 * @param attributeClass rule attribute class
39 * @param <T> type of rule attribute
40 * @return found rule attribute
41 */
42 @SuppressWarnings("unchecked")
43 public <T extends RuleAttribute> Optional<T> findAttribute(final Class<T> attributeClass) {
44 for (RuleAttribute each : attributes) {
45 if (attributeClass.isAssignableFrom(each.getClass())) {
46 return Optional.of((T) each);
47 }
48 }
49 return Optional.empty();
50 }
51
52 /**
53 * Get rule attribute.
54 *
55 * @param attributeClass rule attribute class
56 * @param <T> type of rule attribute
57 * @return got rule attribute
58 */
59 public <T extends RuleAttribute> T getAttribute(final Class<T> attributeClass) {
60 return findAttribute(attributeClass).orElseThrow(() -> new IllegalStateException(String.format("Can not find rule attribute: %s", attributeClass)));
61 }
62 }