1    
2    /* ====================================================================
3     * The Apache Software License, Version 1.1
4     *
5     * Copyright (c) 2002 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 userCode 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 "Apache" and "Apache Software Foundation" and
28    *    "Apache POI" must not be used to endorse or promote products
29    *    derived from this software without prior written permission. For
30    *    written permission, please contact apache@apache.org.
31    *
32    * 5. Products derived from this software may not be called "Apache",
33    *    "Apache POI", nor may "Apache" appear in their name, without
34    *    prior written permission of the Apache Software Foundation.
35    *
36    * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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38    * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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42    * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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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.
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49    *
50    * This software consists of voluntary contributions made by many
51    * individuals on behalf of the Apache Software Foundation.  For more
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53    * <http://www.apache.org/>.
54    */
55   
56   package org.apache.poi.hssf.eventusermodel;
57   
58   import java.util.HashMap;
59   import java.util.List;
60   import java.util.ArrayList;
61   
62   import org.apache.poi.hssf.record.Record;
63   import org.apache.poi.hssf.record.RecordFactory;
64   
65   /**
66    * An HSSFRequest object should be constructed registering an instance or multiple
67    * instances of HSSFListener with each Record.sid you wish to listen for.
68    *
69    * @see org.apache.poi.hssf.eventmodel.HSSFEventFactory
70    * @see org.apache.poi.hssf.eventmodel.HSSFListener
71    * @see org.apache.poi.hssf.dev.EFHSSF
72    * @see org.apache.poi.hssf.HSSFUserException
73    * @author  Andrew C. Oliver (acoliver at apache dot org)
74    * @author Carey Sublette (careysub@earthling.net)
75    */
76   
77   public class HSSFRequest
78   {
79       private HashMap records;
80   
81       /** Creates a new instance of HSSFRequest */
82   
83       public HSSFRequest()
84       {
85           records =
86               new HashMap(50);   // most folks won't listen for too many of these
87       }
88   
89       /**
90        * add an event listener for a particular record type.  The trick is you have to know
91        * what the records are for or just start with our examples and build on them.  Alternatively,
92        * you CAN call addListenerForAllRecords and you'll recieve ALL record events in one listener,
93        * but if you like to squeeze every last byte of efficiency out of life you my not like this.
94        * (its sure as heck what I plan to do)
95        *
96        * @see #addListenerForAllRecords(HSSFListener)
97        *
98        * @param lsnr      for the event
99        * @param sid       identifier for the record type this is the .sid static member on the individual records
100       *        for example req.addListener(myListener, BOFRecord.sid)
101       */
102  
103      public void addListener(HSSFListener lsnr, short sid)
104      {
105          List   list = null;
106          Object obj  = records.get(new Short(sid));
107  
108          if (obj != null)
109          {
110              list = ( List ) obj;
111          }
112          else
113          {
114              list = new ArrayList(
115                  1);   // probably most people will use one listener
116              list.add(lsnr);
117              records.put(new Short(sid), list);
118          }
119      }
120  
121      /**
122       * This is the equivilent of calling addListener(myListener, sid) for EVERY
123       * record in the org.apache.poi.hssf.record package. This is for lazy
124       * people like me. You can call this more than once with more than one listener, but
125       * that seems like a bad thing to do from a practice-perspective unless you have a
126       * compelling reason to do so (like maybe you send the event two places or log it or
127       * something?).
128       *
129       * @param lsnr      a single listener to associate with ALL records
130       */
131  
132      public void addListenerForAllRecords(HSSFListener lsnr)
133      {
134          short[] rectypes = RecordFactory.getAllKnownRecordSIDs();
135  
136          for (int k = 0; k < rectypes.length; k++)
137          {
138              addListener(lsnr, rectypes[ k ]);
139          }
140      }
141  
142  	/**
143  	 * Called by HSSFEventFactory, passes the Record to each listener associated with
144  	 * a record.sid.
145  	 *
146  	 * Exception and return value added 2002-04-19 by Carey Sublette
147  	 *
148  	 * @return numeric user-specified result code. If zero continue processing.
149  	 * @throws HSSFUserException User exception condition
150  	 */
151  
152      protected short processRecord(Record rec) throws HSSFUserException
153      {
154          Object obj = records.get(new Short(rec.getSid()));
155          short userCode = 0;
156  
157          if (obj != null)
158          {
159              List listeners = ( List ) obj;
160  
161              for (int k = 0; k < listeners.size(); k++)
162              {
163                  Object listenObj = listeners.get(k);
164                  if (listenObj instanceof AbortableHSSFListener)
165                  {
166  					AbortableHSSFListener listener = ( AbortableHSSFListener ) listenObj;
167                  	userCode = listener.abortableProcessRecord(rec);
168                  	if (userCode!=0) break;
169  				}
170  				else
171  				{ 
172  					HSSFListener listener = ( HSSFListener ) listenObj;
173  					listener.processRecord(rec);
174  				}
175              }
176          }
177          return userCode;
178      }
179  }
180