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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.commons.jxpath.util;
19  
20  import org.apache.commons.jxpath.BasicNodeSet;
21  import org.apache.commons.jxpath.ExtendedKeyManager;
22  import org.apache.commons.jxpath.JXPathContext;
23  import org.apache.commons.jxpath.KeyManager;
24  import org.apache.commons.jxpath.NodeSet;
25  import org.apache.commons.jxpath.Pointer;
26  import org.apache.commons.jxpath.ri.InfoSetUtil;
27  
28  /**
29   * Utility class.
30   *
31   * @since JXPath 1.3
32   */
33  public class KeyManagerUtils {
34  
35      /**
36       * Adapt KeyManager to implement ExtendedKeyManager.
37       */
38      private static final class SingleNodeExtendedKeyManager implements ExtendedKeyManager {
39  
40          private final KeyManager delegate;
41  
42          /**
43           * Constructs a new SingleNodeExtendedKeyManager.
44           *
45           * @param delegate KeyManager to wrap
46           */
47          public SingleNodeExtendedKeyManager(final KeyManager delegate) {
48              this.delegate = delegate;
49          }
50  
51          @Override
52          public NodeSet getNodeSetByKey(final JXPathContext context, final String key, final Object value) {
53              final Pointer pointer = delegate.getPointerByKey(context, key, InfoSetUtil.stringValue(value));
54              final BasicNodeSet result = new BasicNodeSet();
55              result.add(pointer);
56              return result;
57          }
58  
59          @Override
60          public Pointer getPointerByKey(final JXPathContext context, final String keyName, final String keyValue) {
61              return delegate.getPointerByKey(context, keyName, keyValue);
62          }
63      }
64  
65      /**
66       * Gets an ExtendedKeyManager from the specified KeyManager.
67       *
68       * @param keyManager to adapt, if necessary
69       * @return {@code keyManager} if it implements ExtendedKeyManager or a basic single-result ExtendedKeyManager that delegates to {@code keyManager}.
70       */
71      public static ExtendedKeyManager getExtendedKeyManager(final KeyManager keyManager) {
72          return keyManager instanceof ExtendedKeyManager ? (ExtendedKeyManager) keyManager : new SingleNodeExtendedKeyManager(keyManager);
73      }
74  
75      /**
76       * Constructs a new instance.
77       *
78       * @deprecated Will be private in the next major version.
79       */
80      @Deprecated
81      public KeyManagerUtils() {
82          // empty
83      }
84  }