KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > net > sf > jga > parser > EnumHandler


1 // ============================================================================
2 // $Id: EnumHandler.java,v 1.4 2005/08/02 23:45:05 davidahall Exp $
3 // Copyright (c) 2005 David A. Hall
4 // ============================================================================
5 // The contents of this file are subject to the Common Development and
6 // Distribution License (CDDL), Version 1.0 (the License); you may not use this
7 // file except in compliance with the License. You should have received a copy
8 // of the the License along with this file: if not, a copy of the License is
9 // available from Sun Microsystems, Inc.
10 //
11 // http://www.sun.com/cddl/cddl.html
12 //
13 // From time to time, the license steward (initially Sun Microsystems, Inc.) may
14 // publish revised and/or new versions of the License. You may not use,
15 // distribute, or otherwise make this file available under subsequent versions
16 // of the License.
17 //
18 // Alternatively, the contents of this file may be used under the terms of the
19 // GNU Lesser General Public License Version 2.1 or later (the "LGPL"), in which
20 // case the provisions of the LGPL are applicable instead of those above. If you
21 // wish to allow use of your version of this file only under the terms of the
22 // LGPL, and not to allow others to use your version of this file under the
23 // terms of the CDDL, indicate your decision by deleting the provisions above
24 // and replace them with the notice and other provisions required by the LGPL.
25 // If you do not delete the provisions above, a recipient may use your version
26 // of this file under the terms of either the CDDL or the LGPL.
27 //
28 // This library is distributed in the hope that it will be useful,
29 // but WITHOUT ANY WARRANTY; without even the implied warranty of
30 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
31 // ============================================================================
32
33 package net.sf.jga.parser;
34
35 import java.text.MessageFormat JavaDoc;
36 import net.sf.jga.fn.adaptor.Constant;
37
38 /**
39  * Service class that tests if the type is an enum and the name is one of the
40  * values of the enumeration. This class exists and is kept trivially small
41  * in order to support Java 1.4 and 1.5 from a single codebase: the build
42  * procedure replaces this class with a dummy that does not require a Java 1.5
43  * Class.class file be available.
44  * <p>
45  * Copyright &copy; 2005 David A. Hall
46  */
47
48 class EnumHandler {
49     static final boolean handlesEnums = true;
50     
51     static FunctorRef checkEnum(Class JavaDoc type, String JavaDoc name) throws ParseException {
52         if (type.isEnum()) {
53             try {
54                 return new GeneratorRef(new Constant(Enum.valueOf(type, name)), type);
55             }
56             catch (IllegalArgumentException JavaDoc x) {
57                 String JavaDoc msg = "enum {0} has no {1} value";
58                 Object JavaDoc[] args = new Object JavaDoc[] { type.getName(), name };
59                 ParseException px = new ParseException(MessageFormat.format(msg, args));
60                 px.initCause(x);
61                 throw px;
62             }
63         }
64
65         return null;
66     }
67 }
68
Popular Tags