1 /* VMVio.java -- Native operations, required by value IO.
2  Copyright (C) 2005 Free Software Foundation, Inc.
3 
4  This file is part of GNU Classpath.
5 
6  GNU Classpath is free software; you can redistribute it and/or modify
7  it under the terms of the GNU General Public License as published by
8  the Free Software Foundation; either version 2, or (at your option)
9  any later version.
10 
11  GNU Classpath is distributed in the hope that it will be useful, but
12  WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  General Public License for more details.
15 
16  You should have received a copy of the GNU General Public License
17  along with GNU Classpath; see the file COPYING.  If not, write to the
18  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19  02110-1301 USA.
20 
21  Linking this library statically or dynamically with other modules is
22  making a combined work based on this library.  Thus, the terms and
23  conditions of the GNU General Public License cover the whole
24  combination.
25 
26  As a special exception, the copyright holders of this library give you
27  permission to link this library with independent modules to produce an
28  executable, regardless of the license terms of these independent
29  modules, and to copy and distribute the resulting executable under
30  terms of your choice, provided that you also meet, for each linked
31  independent module, the terms and conditions of the license of that
32  module.  An independent module is a module which is not derived from
33  or based on this library.  If you modify this library, you may extend
34  this exception to your version of the library, but you are not
35  obligated to do so.  If you do not wish to do so, delete this
36  exception statement from your version. */
37 
38 /**
39  * This is a temporary replacement for the native call that would allocate
40  * objects without public constructors. The replacement only allocates
41  * objects with public parameterless constructor and objects with public
42  * constructor taking string (like some Throwables).
43  *
44  * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
45  *
46  * TODO FIXME replace by native call like in VMObjectInputStream.
47  * Required modification of Classpath the build system.
48  */
49 
50 
51 package gnu.CORBA.CDR;
52 
53 import java.lang.reflect.Constructor;
54 
55 public class VMVio
56 {
57   /**
58    * Allocates a new Object of type clazz but without running the default
59    * constructor on it. It then calls the given constructor on it. The given
60    * constructor method comes from the constr_clazz which is a super class of
61    * the given clazz.
62    */
allocateObject(Class clazz, Class constr_clazz, Constructor constructor)63   public static Object allocateObject(Class clazz, Class constr_clazz,
64     Constructor constructor)
65     throws InstantiationException
66   {
67     try
68       {
69         Constructor c = clazz.getConstructor(new Class[0]);
70         c.setAccessible(true);
71         return c.newInstance(new Object[0]);
72       }
73     catch (Exception ex)
74       {
75         try
76           {
77             Constructor c = clazz.getConstructor(new Class[] { String.class });
78             return c.newInstance(new Object[] { "" });
79           }
80         catch (Exception ex2)
81           {
82             Constructor c[] = clazz.getConstructors();
83 
84             for (int i = 0; i < c.length; i++)
85               {
86                 try
87                   {
88                     c[i].setAccessible(true);
89                     Class[] args = c[i].getParameterTypes();
90                     return c[i].newInstance(new Object[args.length]);
91                   }
92                 catch (Exception ex3)
93                   {
94                     // Try another one.
95                   }
96               }
97           }
98         throw new InstantiationException(clazz.getName());
99       }
100   }
101 }
102