Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
EvaluationExceptionHandler |
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| 1.0;1 |
1 | /* | |
2 | * Copyright (C) 1998-2001 Semiotek Inc. All Rights Reserved. | |
3 | * | |
4 | * Redistribution and use in source and binary forms, with or without | |
5 | * modification, are permitted under the terms of either of the following | |
6 | * Open Source licenses: | |
7 | * | |
8 | * The GNU General Public License, version 2, or any later version, as | |
9 | * published by the Free Software Foundation | |
10 | * (http://www.fsf.org/copyleft/gpl.html); | |
11 | * | |
12 | * or | |
13 | * | |
14 | * The Semiotek Public License (http://webmacro.org/LICENSE.) | |
15 | * | |
16 | * This software is provided "as is", with NO WARRANTY, not even the | |
17 | * implied warranties of fitness to purpose, or merchantability. You | |
18 | * assume all risks and liabilities associated with its use. | |
19 | * | |
20 | * See www.webmacro.org for more information on the WebMacro project. | |
21 | */ | |
22 | ||
23 | ||
24 | /** | |
25 | * EvaluationExceptionHandler | |
26 | * | |
27 | * An interface for specifying how certain classes of errors will be | |
28 | * handled. The handle method is called when an exception is thrown | |
29 | * when trying to expand a variable or property reference. The error | |
30 | * and warning methods are called from directives and context tools to | |
31 | * generate output warnings. Any of these routines may throw exceptions, | |
32 | * in which case the enclosing servlet will catch it and generate an error | |
33 | * which the user sees (useful for debugging.) | |
34 | * | |
35 | * @author Brian Goetz | |
36 | * @since 0.96 */ | |
37 | ||
38 | package org.webmacro.engine; | |
39 | ||
40 | import org.webmacro.Broker; | |
41 | import org.webmacro.Context; | |
42 | import org.webmacro.PropertyException; | |
43 | import org.webmacro.util.Settings; | |
44 | ||
45 | /** | |
46 | * Handler for Exceptions generated during property evaluation. | |
47 | * | |
48 | * @since 0.96 | |
49 | * | |
50 | */ | |
51 | public interface EvaluationExceptionHandler | |
52 | { | |
53 | ||
54 | /** | |
55 | * Initialize the EEH. | |
56 | */ | |
57 | public void init (Broker b, Settings config); | |
58 | ||
59 | /** | |
60 | * When an exception is detected in the process of expanding (writing) | |
61 | * a variable reference, this method is consulted. It either throws | |
62 | * an exception, or it returns a String which can be written to the | |
63 | * output in place of the property expansion. | |
64 | */ | |
65 | public String expand (Variable variable, | |
66 | Context context, | |
67 | Exception problem) | |
68 | throws PropertyException; | |
69 | ||
70 | /** | |
71 | * When an exception is detected in the process of evaluating | |
72 | * a variable reference, this method is consulted. It either returns, | |
73 | * in which case the caller is supposed to supply a default value (like | |
74 | * null), or will throw. | |
75 | */ | |
76 | public void evaluate (Variable variable, | |
77 | Context context, | |
78 | Exception problem) | |
79 | throws PropertyException; | |
80 | ||
81 | public String warningString (String warningText) | |
82 | throws PropertyException; | |
83 | ||
84 | public String errorString (String errorText) | |
85 | throws PropertyException; | |
86 | ||
87 | } |