View Javadoc
1   package org.codehaus.plexus.interpolation;
2   
3   /*
4    * Copyright 2001-2008 Codehaus Foundation.
5    *
6    * Licensed under the Apache License, Version 2.0 (the "License");
7    * you may not use this file except in compliance with the License.
8    * You may obtain a copy of the License at
9    *
10   *      http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  /**
20   * Signals an unrecoverable error in the process of interpolating a string, such
21   * as the detection of an expression cycle. Errors resolving individual values
22   * from expressions, such as those that happen when an object wrapped in an
23   * {@link ObjectBasedValueSource} doesn't have the property represented by a
24   * particular expression part, should <b>NOT</b> result in InterpolationExceptions
25   * being thrown. Instead, they should be reported in the feedback from the {@link ValueSource},
26   * which is propagated out through {@link Interpolator#getFeedback()}.
27   * 
28   */
29  public class InterpolationException
30      extends Exception
31  {
32  
33      private static final long serialVersionUID = 1L;
34      
35      private final String expression;
36  
37      /**
38       * @param message The general description of the problem
39       * @param expression The expression that triggered the problem
40       * @param cause The wrapped exception
41       */
42      public InterpolationException( String message,
43                                        String expression,
44                                        Throwable cause )
45      {
46          super( buildMessage( message, expression ), cause );
47          this.expression = expression;
48      }
49  
50      /**
51       * @param message The general description of the problem
52       * @param expression The expression that triggered the problem
53       */
54      public InterpolationException( String message, String expression )
55      {
56          super( buildMessage( message, expression ) );
57          this.expression = expression;
58      }
59  
60      private static String buildMessage( String message,
61                                          String expression )
62      {
63          return "Resolving expression: '" + expression + "': " + message;
64      }
65  
66      /**
67       * @return The expression that triggered this exception.
68       */
69      public String getExpression()
70      {
71          return expression;
72      }
73  
74  }