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1 /*
2  * The Apache Software License, Version 1.1
3  *
4  *
5  * Copyright (c) 2001-2003 The Apache Software Foundation. All rights
6  * reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  * notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  * notice, this list of conditions and the following disclaimer in
17  * the documentation and/or other materials provided with the
18  * distribution.
19  *
20  * 3. The end-user documentation included with the redistribution,
21  * if any, must include the following acknowledgment:
22  * "This product includes software developed by the
23  * Apache Software Foundation (http://www.apache.org/)."
24  * Alternately, this acknowledgment may appear in the software itself,
25  * if and wherever such third-party acknowledgments normally appear.
26  *
27  * 4. The names "Axis" and "Apache Software Foundation" must
28  * not be used to endorse or promote products derived from this
29  * software without prior written permission. For written
30  * permission, please contact apache@apache.org.
31  *
32  * 5. Products derived from this software may not be called "Apache",
33  * nor may "Apache" appear in their name, without prior written
34  * permission of the Apache Software Foundation.
35  *
36  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
37  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
38  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
39  * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
40  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
42  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
43  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
44  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
45  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
46  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
47  * SUCH DAMAGE.
48  * ====================================================================
49  *
50  * This software consists of voluntary contributions made by many
51  * individuals on behalf of the Apache Software Foundation. For more
52  * information on the Apache Software Foundation, please see
53  * <http://www.apache.org/>.
54  */
55 package org.jboss.axis.utils.bytecode;
56
57 import org.jboss.axis.utils.Messages;
58 import org.jboss.logging.Logger;
59
60 import java.io.IOException JavaDoc;
61 import java.lang.reflect.Method JavaDoc;
62 import java.lang.reflect.Proxy JavaDoc;
63
64 /**
65  * This class retieves function parameter names from bytecode built with
66  * debugging symbols. Used as a last resort when creating WSDL.
67  *
68  * @author <a HREF="mailto:tomj@macromedia.com">Tom Jordahl</a>
69  */
70 public class ParamNameExtractor
71 {
72
73    private static Logger log = Logger.getLogger(ParamNameExtractor.class.getName());
74
75    /**
76     * Retrieve a list of function parameter names from a method
77     * Returns null if unable to read parameter names (i.e. bytecode not
78     * built with debug).
79     */
80    public static String JavaDoc[] getParameterNamesFromDebugInfo(Method JavaDoc method)
81    {
82       // Don't worry about it if there are no params.
83 int numParams = method.getParameterTypes().length;
84       if (numParams == 0)
85          return null;
86
87       // get declaring class
88 Class JavaDoc c = method.getDeclaringClass();
89
90       // Don't worry about it if the class is a Java dynamic proxy
91 if (Proxy.isProxyClass(c))
92       {
93          return null;
94       }
95
96       try
97       {
98          // get a parameter reader
99 ParamReader pr = new ParamReader(c);
100          // get the paramter names
101 String JavaDoc[] names = pr.getParameterNames(method);
102          return names;
103       }
104       catch (IOException JavaDoc e)
105       {
106          // log it and leave
107 log.info(Messages.getMessage("error00") + ":" + e);
108          return null;
109       }
110    }
111 }
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