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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.jexl2.internal;
19  import java.util.Map;
20  import java.lang.reflect.InvocationTargetException;
21  /**
22   * Specialized executor to set a property in a Map.
23   * @since 2.0
24   */
25  public final class MapSetExecutor extends AbstractExecutor.Set {
26      /** The java.util.map.put method used as an active marker in MapSet. */
27      private static final java.lang.reflect.Method MAP_SET = initMarker(Map.class, "put", Object.class, Object.class);
28      /** The property. */
29      private final Object property;
30  
31      /**
32       * Creates an instance checking for the Map interface.
33       *@param is the introspector
34       *@param clazz the class that might implement the map interface
35       *@param key the key to use as argument in map.put(key,value)
36       *@param value the value to use as argument in map.put(key,value)
37      */
38      public MapSetExecutor(Introspector is, Class<?> clazz, Object key, Object value) {
39          super(clazz, discover(clazz));
40          property = key;
41      }
42  
43      /** {@inheritDoc} */
44      @Override
45      public Object getTargetProperty() {
46          return property;
47      }
48      
49      /** {@inheritDoc} */
50      @Override
51      public Object execute(final Object obj, Object value)
52      throws IllegalAccessException, InvocationTargetException {
53          @SuppressWarnings("unchecked") // ctor only allows Map instances - see discover() method
54          final Map<Object,Object> map = ((Map<Object, Object>) obj);
55          map.put(property, value);
56          return value;
57      }
58  
59      /** {@inheritDoc} */
60      @Override
61      public Object tryExecute(final Object obj, Object key, Object value) {
62          if (obj != null && method != null
63              && objectClass.equals(obj.getClass())
64              && (key == null || property.getClass().equals(key.getClass()))) {
65              @SuppressWarnings("unchecked") // ctor only allows Map instances - see discover() method
66              final Map<Object,Object> map = ((Map<Object, Object>) obj);
67              map.put(key, value);
68              return value;
69          }
70          return TRY_FAILED;
71      }
72  
73      /**
74       * Finds the method to perform 'set' on a map.
75       * @param clazz the class to introspect
76       * @return a marker method, map.get
77       */
78      static java.lang.reflect.Method discover(Class<?> clazz) {
79          return (Map.class.isAssignableFrom(clazz))? MAP_SET : null;
80      }
81  }