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1   /* 
2    * Copyright (c) 2007, Fraunhofer-Gesellschaft
3    * All rights reserved.
4    * 
5    * Redistribution and use in source and binary forms, with or without
6    * modification, are permitted provided that the following conditions are
7    * met:
8    * 
9    * (1) Redistributions of source code must retain the above copyright
10   *     notice, this list of conditions and the disclaimer at the end.
11   *     Redistributions in binary form must reproduce the above copyright
12   *     notice, this list of conditions and the following disclaimer in
13   *     the documentation and/or other materials provided with the
14   *     distribution.
15   * 
16   * (2) Neither the name of Fraunhofer nor the names of its
17   *     contributors may be used to endorse or promote products derived
18   *     from this software without specific prior written permission.
19   * 
20   * DISCLAIMER
21   * 
22   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33   *  
34   */
35  package org.ogf.graap.wsag.server.monitoring;
36  
37  import java.text.MessageFormat;
38  import java.util.HashMap;
39  import java.util.Map;
40  
41  import org.apache.commons.jexl2.JexlContext;
42  
43  /**
44   * An implementation of the {@link JexlContext}. In contrast to the default implementation this specific
45   * implementation throws an {@link IllegalStateException} if a non-existing variable is resolved from the
46   * context. This prevents that default values are used for non-existing variables during expression
47   * evaluation.
48   * 
49   * @author Oliver Waeldrich
50   * 
51   */
52  public class JEXLWSAG4JContext extends HashMap<String, Object> implements JexlContext
53  {
54  
55      private static final long serialVersionUID = 1L;
56  
57      /**
58       * Sets a list variables for this context at once.
59       * 
60       * @param map
61       *            the parameters to set
62       * 
63       * @see JexlContext#set(String, Object)
64       */
65      public void setVars( Map<String, Object> map )
66      {
67          clear();
68          putAll( map );
69      }
70  
71      /**
72       * {@inheritDoc}
73       */
74      public Object get( String key )
75      {
76          Object result = super.get( key );
77  
78          if ( result == null )
79          {
80              throw new IllegalStateException(
81                                               MessageFormat.format( "Unable to resolve value for variable {0}",
82                                                                     new Object[] { key } ) );
83          }
84  
85          return result;
86      }
87  
88      /**
89       * {@inheritDoc}
90       * 
91       * @see org.apache.commons.jexl2.JexlContext#has(java.lang.String)
92       */
93      public boolean has( String key )
94      {
95          return containsKey( key );
96      }
97  
98      /**
99       * {@inheritDoc}
100      * 
101      * @see org.apache.commons.jexl2.JexlContext#set(java.lang.String, java.lang.Object)
102      */
103     public void set( String name, Object value )
104     {
105         super.put( name, value );
106     }
107 
108 }