Source for gnu.inet.nntp.GroupIterator

   1: /*
   2:  * GroupIterator.java
   3:  * Copyright (C) 2002 The Free Software Foundation
   4:  * 
   5:  * This file is part of GNU inetlib, a library.
   6:  * 
   7:  * GNU inetlib is free software; you can redistribute it and/or modify
   8:  * it under the terms of the GNU General Public License as published by
   9:  * the Free Software Foundation; either version 2 of the License, or
  10:  * (at your option) any later version.
  11:  * 
  12:  * GNU inetlib 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
  15:  * GNU General Public License for more details.
  16:  * 
  17:  * You should have received a copy of the GNU General Public License
  18:  * along with this library; if not, write to the Free Software
  19:  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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:  * obliged to do so.  If you do not wish to do so, delete this
  36:  * exception statement from your version.
  37:  */
  38: 
  39: package gnu.inet.nntp;
  40: 
  41: import java.io.IOException;
  42: import java.util.NoSuchElementException;
  43: 
  44: /**
  45:  * An iterator over an NNTP newsgroup listing.
  46:  *
  47:  * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
  48:  */
  49: public class GroupIterator
  50:   extends LineIterator
  51: {
  52: 
  53:   static final String CAN_POST = "y";
  54: 
  55:   GroupIterator(NNTPConnection connection)
  56:   {
  57:     super(connection);
  58:   }
  59: 
  60:   /**
  61:    * Returns the next group.
  62:    */
  63:   public Object next()
  64:   {
  65:     try
  66:       {
  67:         return nextGroup();
  68:       }
  69:     catch (IOException e)
  70:       {
  71:         throw new NoSuchElementException("I/O error: " + e.getMessage());
  72:       }
  73:   }
  74: 
  75:   /**
  76:    * Returns the next group.
  77:    */
  78:   public Group nextGroup()
  79:     throws IOException
  80:   {
  81:     String line = nextLine();
  82: 
  83:     // Parse line
  84:     int start = 0, end;
  85:     end = line.indexOf(' ', start);
  86:     String name = line.substring(start, end);
  87:     start = end + 1;
  88:     end = line.indexOf(' ', start);
  89:     int last = Integer.parseInt(line.substring(start, end));
  90:     start = end + 1;
  91:     end = line.indexOf(' ', start);
  92:     int first = Integer.parseInt(line.substring(start, end));
  93:     start = end + 1;
  94:     boolean canPost = CAN_POST.equals(line.substring(start));
  95: 
  96:     return new Group(name, last, first, canPost);
  97:   }
  98: 
  99: }