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1   package org.apache.commons.ognl;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   * http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import org.apache.commons.ognl.enhance.UnsupportedCompilationException;
23  
24  /**
25   * $Id: ASTEval.java 1235614 2012-01-25 03:31:12Z mcucchiara $
26   * @author Luke Blanshard (blanshlu@netscape.net)
27   * @author Drew Davidson (drew@ognl.org)
28   */
29  class ASTEval
30      extends SimpleNode
31  {
32  
33      public ASTEval( int id )
34      {
35          super( id );
36      }
37  
38      public ASTEval( OgnlParser p, int id )
39      {
40          super( p, id );
41      }
42  
43      protected Object getValueBody( OgnlContext context, Object source )
44          throws OgnlException
45      {
46          Object result, expr = children[0].getValue( context, source ), previousRoot = context.getRoot();
47          Node node;
48  
49          source = children[1].getValue( context, source );
50          node = ( expr instanceof Node ) ? (Node) expr : (Node) Ognl.parseExpression( expr.toString() );
51          try
52          {
53              context.setRoot( source );
54              result = node.getValue( context, source );
55          }
56          finally
57          {
58              context.setRoot( previousRoot );
59          }
60          return result;
61      }
62  
63      protected void setValueBody( OgnlContext context, Object target, Object value )
64          throws OgnlException
65      {
66          Object expr = children[0].getValue( context, target ), previousRoot = context.getRoot();
67          Node node;
68  
69          target = children[1].getValue( context, target );
70          node = ( expr instanceof Node ) ? (Node) expr : (Node) Ognl.parseExpression( expr.toString() );
71          try
72          {
73              context.setRoot( target );
74              node.setValue( context, target, value );
75          }
76          finally
77          {
78              context.setRoot( previousRoot );
79          }
80      }
81  
82      public String toGetSourceString( OgnlContext context, Object target )
83      {
84          throw new UnsupportedCompilationException( "Eval expressions not supported as native java yet." );
85      }
86  
87      public String toSetSourceString( OgnlContext context, Object target )
88      {
89          throw new UnsupportedCompilationException( "Map expressions not supported as native java yet." );
90      }
91      
92      public <R, P> R accept( NodeVisitor<? extends R, ? super P> visitor, P data )
93          throws OgnlException
94      {
95          return visitor.visit( this, data );
96      }
97  
98      @Override
99      public boolean isEvalChain( OgnlContext context )
100         throws OgnlException
101     {
102         return true;
103     }
104 }