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1   /*
2    * Copyright (c) 2005 The University of Reading
3    * All rights reserved.
4    *
5    * Redistribution and use in source and binary forms, with or without
6    * modification, are permitted provided that the following conditions
7    * are met:
8    * 1. Redistributions of source code must retain the above copyright
9    *    notice, this list of conditions and the following disclaimer.
10   * 2. Redistributions in binary form must reproduce the above copyright
11   *    notice, this list of conditions and the following disclaimer in the
12   *    documentation and/or other materials provided with the distribution.
13   * 3. Neither the name of the University of Reading, nor the names of the
14   *    authors or contributors may be used to endorse or promote products
15   *    derived from this software without specific prior written permission.
16   *
17   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20   * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27   */
28  
29  package uk.ac.rdg.resc.jstyx.client.callbacks;
30  
31  import uk.ac.rdg.resc.jstyx.client.StyxConnection;
32  import uk.ac.rdg.resc.jstyx.client.CStyxFile;
33  import uk.ac.rdg.resc.jstyx.client.MessageCallback;
34  
35  import uk.ac.rdg.resc.jstyx.messages.StyxMessage;
36  import uk.ac.rdg.resc.jstyx.messages.RwalkMessage;
37  import uk.ac.rdg.resc.jstyx.messages.RstatMessage;
38  import uk.ac.rdg.resc.jstyx.messages.RopenMessage;
39  import uk.ac.rdg.resc.jstyx.messages.RcreateMessage;
40  
41  /***
42   * Callback used by CStyxFile.openOrCreateAsync()
43   *
44   * @author jdb
45   * $Revision: 353 $
46   * $Date: 2005-08-10 19:33:48 +0100 (Wed, 10 Aug 2005) $
47   * $Log$
48   * Revision 1.2  2005/08/10 18:33:48  jonblower
49   * Bug fixes
50   *
51   * Revision 1.1  2005/08/05 13:46:40  jonblower
52   * Factored out all callback objects from CStyxFile into separate classes
53   *
54   */
55  
56  public class OpenOrCreateCallback extends MessageCallback
57  {
58      private boolean isDirectory;
59      private int mode;
60      private MessageCallback callback;
61      private CStyxFile file;
62      private StyxConnection conn;
63  
64      public OpenOrCreateCallback(CStyxFile file, boolean isDirectory, int mode,
65          MessageCallback callback)
66      {
67          this.file = file;
68          this.conn = this.file.getConnection();
69          this.isDirectory = isDirectory;
70          this.mode = mode;
71          this.callback = callback;
72      }
73  
74      public void nextStage()
75      {
76          // We must first find out if this is a file or directory (will also
77          // test to see if it exists)
78          if (this.file.hasFid())
79          {
80              // See if we have a Qid, so that we can work out whether this is 
81              // a file or directory
82              if (this.file.getQid() == null)
83              {
84                  this.file.refreshAsync(this);
85              }
86              else
87              {
88                  // Check to see if it is the right type of file (i.e. file or
89                  // directory)
90                  if (this.isDirectory == (this.file.getQid().getType() == 128))
91                  {
92                      // Now we can open the file
93                      this.file.openAsync(this.mode, this);
94                  }
95                  else
96                  {
97                      String errMsg = this.file.getPath() + " already exists as a " +
98                          ((this.file.getQid().getType() == 128) ? "directory" : "file");
99                      this.error(errMsg, null);
100                 }
101             }
102         }
103         else
104         {
105             // We don't have a fid for the file yet
106             this.file.walkFidAsync(this);
107         }
108     }
109 
110     public void replyArrived(StyxMessage rMessage, StyxMessage tMessage)
111     {
112         if (rMessage instanceof RwalkMessage)
113         {
114             // We've just successfully walked to the file so we have a fid
115             // and it must exist.  Move to the next stage (checking for existence
116             // of a qid)
117             this.nextStage();
118         }
119         else if (rMessage instanceof RstatMessage)
120         {
121             // We've just successfully got the stat of the file, so we have
122             // the qid. Move to the next stage (i.e. checking
123             // the file type)
124             this.nextStage();
125         }
126         else if (rMessage instanceof RopenMessage)
127         {
128             // We've just opened the file.
129             if (this.callback != null)
130             {
131                 this.callback.replyArrived(rMessage, tMessage);
132             }
133             else
134             {
135                 this.file.fireOpen();
136             }
137         }
138         else if (rMessage instanceof RcreateMessage)
139         {
140             // Must be an RcreateMessage
141             if (this.callback != null)
142             {
143                 this.callback.replyArrived(rMessage, tMessage);
144             }
145             else
146             {
147                 this.file.fireCreated();
148             }
149         }
150     }
151 
152     public void error(String message, StyxMessage tMessage)
153     {
154         if (!this.file.hasFid())
155         {
156             // The file does not exist
157             int perm = this.isDirectory ? 0777 : 0666;
158             this.file.createAsync(this.isDirectory, perm, this.mode, this);
159         }
160         else if (this.callback != null)
161         {
162             this.callback.error(message, tMessage);
163         }
164         else
165         {
166             this.file.fireError(message);
167         }
168     }
169 }