Indentor


1   /*====================================================================
2   
3   OpenCCM: The Open CORBA Component Model Platform
4   Copyright (C) 2000-2004 INRIA & USTL - LIFL - GOAL
5   Contact: openccm@objectweb.org
6   
7   This library is free software; you can redistribute it and/or
8   modify it under the terms of the GNU Lesser General Public
9   License as published by the Free Software Foundation; either
10  version 2.1 of the License, or any later version.
11  
12  This library is distributed in the hope that it will be useful,
13  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  Lesser General Public License for more details.
16  
17  You should have received a copy of the GNU Lesser General Public
18  License along with this library; if not, write to the Free Software
19  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
20  USA
21  
22  Initial developer(s): Christophe Demarey.
23  Contributor(s): .
24  
25  ====================================================================*/
26  
27  package org.objectweb.openccm.generator.common.lib;
28  
29  /**
30   * This a utility class to indent files.
31   */
32  public class Indentor
33  {
34      // ===========================================================
35      //
36      // Constants.
37      //
38      // ===========================================================
39  
40      /**
41       ** The number of spaces to print for an indentation
42       **/
43      public static final int NB_CAR_INDENT = 4;
44  
45      /**
46       ** The tag used to increment indentation
47       **/
48      public static final String   INCREMENT_TAG = new String  ("/inc");
49  
50      /**
51       ** The tag used to decrement indentation
52       **/
53      public static final String   DECREMENT_TAG = new String  ("/dec");
54  
55      /**
56       ** The end-line tag
57       **/
58      public static final String   END_LINE = new String  ("\n");
59  
60      // ===========================================================
61      //
62      // Internal State.
63      //
64      // ===========================================================
65  
66      /**
67       ** The number of indentation to do
68       **/
69      private int indent_;
70  
71      /**
72       ** The input stream to indent
73       **/
74      private java.io.BufferedReader   in_;
75  
76      /**
77       ** The resulting output
78       **/
79      private java.util.List   out_;
80  
81      // ===========================================================
82      //
83      // Constructors.
84      //
85      // ===========================================================
86  
87      /**
88       * The default constructor
89       */
90      public Indentor() {}
91  
92      // ===========================================================
93      //
94      // Internal methods.
95      //
96      // ===========================================================
97  
98      /**
99       * Initialize the indentor
100      *
101      * @param file_name - The file to indent.
102      */
103     private void
104     init(String   file_name)
105     {
106         // init internal states
107         indent_ = 0;
108         in_ = null;
109         out_ = new java.util.ArrayList  ();
110 
111         // init input file
112         try{
113             in_ = new java.io.BufferedReader  ( new java.io.FileReader  (file_name) );
114         }catch(java.io.IOException   ex){
115             System.err.println("I/O error : ");
116             ex.printStackTrace();
117         }
118     }
119 
120     /**
121      * Our own little min method.
122      *
123      * @param a - An integer value.
124      * @param b - An integer value.
125      *
126      * @return The min value.
127      **/
128     private int
129     min(int a, int b)
130     {
131         if (a < b) return a;
132             return b;
133     }
134 
135     /**
136      * Search the first occurence between :
137      *  - INCREMENT_TAG
138      *  - DECREMENT_TAG
139      *  - END_LINE
140      *
141      * @param src - The string to search in.
142      *
143      * @return The index of the first occurence found, else -1.
144      **/
145     private int searchFirst(String   src)
146     {
147         int index_inc = -1;
148         int index_dec = -1;
149         int index_end = -1;
150 
151         index_inc = src.indexOf(INCREMENT_TAG);
152         index_dec = src.indexOf(DECREMENT_TAG);
153         index_end = src.indexOf(END_LINE);
154         if (index_inc != -1)
155         {
156             if (index_dec != -1)
157             {
158                 if (index_end != -1)
159                 {
160                     if (index_inc < index_dec)
161                         return min(index_inc, index_end);
162                     else
163                         return min(index_dec, index_end);
164                 }
165                 else
166                 {
167                     return min(index_inc, index_dec);
168                 }
169             }
170             else
171             {
172                 if (index_end != -1)
173                     return min(index_inc, index_end);
174                 else
175                     return index_inc;
176             }
177         }
178         else if (index_dec != -1)
179         {
180             if (index_end != -1)
181             {
182                 return min(index_dec, index_end);
183             }
184             else
185             {
186                 return index_dec;
187             }
188         }
189         else
190         {
191             return index_end;
192         }
193 
194     }
195 
196     /**
197      * Increment the output
198      **/
199     private void
200     increment()
201     {
202         indent_ += NB_CAR_INDENT;
203     }
204 
205     /**
206      * Decrement the output
207      **/
208     private void
209     decrement()
210     {
211         indent_ -= NB_CAR_INDENT;
212         if(indent_ < 0)
213             indent_ = 0;
214     }
215 
216     // ===========================================================
217     //
218     // Public methods.
219     //
220     // ===========================================================
221 
222     /**
223      * Replace the first occurence found in str with the new string
224      *
225      * @param str - The string to search in.
226      * @param old_pattern - The pattern to search.
227      * @param new_pattern - The replacing pattern.
228      *
229      * @return The resulting string.
230      **/
231     public String  
232     replaceFirst(String   str, String   old_pattern, String   new_pattern)
233     {
234         int index = str.indexOf(old_pattern);
235         int l = old_pattern.length();
236         try{
237             return str.substring(0, index) + new_pattern
238                    + str.substring(index+l, str.length());
239         }catch(Exception   e){
240             return str;
241         }
242     }
243 
244     /**
245      * Management of indentation
246      *
247      * @param file_name - The file to indent.
248      **/
249     public void
250     indent(String   file_name) throws java.io.IOException  
251     {
252         String   current = null;
253 
254         // Init the indentor
255         init(file_name);
256 
257         // Processing the file
258         while ( (current = in_.readLine() ) != null )
259         {
260             // Indent the new line
261             String   res = new String  ("");
262 
263             for(int i=0; i<indent_; i++)
264                 res += " ";
265 
266             // Search incrementation / decrementation tag
267             int index = searchFirst(current);
268 
269             // Generate indentation
270             if ( current.startsWith(INCREMENT_TAG, index) )
271             {
272                 increment();
273                 current = replaceFirst(current, INCREMENT_TAG, "");
274             }
275             else if( current.startsWith(DECREMENT_TAG, index) )
276             {
277                 decrement();
278                 current = replaceFirst(current, DECREMENT_TAG, "");
279                 res = new String  ("");
280                 for(int i=0; i<indent_; i++)
281                     res += " ";
282             }
283             res += current + END_LINE;
284             out_.add( res );
285         }
286 
287         in_.close();
288         apply(file_name);
289     }
290 
291     /**
292      * Apply changes on the file
293      *
294      * @param file_name - The file to indent.
295      **/
296     public void
297     apply(String   file_name)
298     {
299         java.io.File   fic = null;
300         java.io.PrintWriter   writer = null;
301 
302         // Overwrite the input file
303         try{
304             fic = new java.io.File  (file_name);
305             fic.delete();
306 
307             writer = new java.io.PrintWriter  ( new java.io.FileWriter  (fic) );
308         }catch(java.io.IOException   ex){
309             System.err.println("I/O error : ");
310             ex.printStackTrace();
311         }
312 
313         // Print contents
314         for(int i=0; i<out_.size(); i++)
315         {
316             writer.write( (String  )out_.get(i) );
317         }
318         writer.flush();
319         writer.close();
320     }
321 
322 }
323 
324
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