| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| EvaluationExceptionHandler |
|
| 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 | } |