Lucene.Net/Index/SegmentInfos.cs

   1 using System.Collections;
   2 using Lucene.Net.Store;
   3
   4 namespace Lucene.Net.Index
   5 {
   6         /* ====================================================================
   7          * The Apache Software License, Version 1.1
   8          *
   9          * Copyright (c) 2001 The Apache Software Foundation.  All rights
  10          * reserved.
  11          *
  12          * Redistribution and use in source and binary forms, with or without
  13          * modification, are permitted provided that the following conditions
  14          * are met:
  15          *
  16          * 1. Redistributions of source code must retain the above copyright
  17          *    notice, this list of conditions and the following disclaimer.
  18          *
  19          * 2. Redistributions in binary form must reproduce the above copyright
  20          *    notice, this list of conditions and the following disclaimer in
  21          *    the documentation and/or other materials provided with the
  22          *    distribution.
  23          *
  24          * 3. The end-user documentation included with the redistribution,
  25          *    if any, must include the following acknowledgment:
  26          *       "This product includes software developed by the
  27          *        Apache Software Foundation (http://www.apache.org/)."
  28          *    Alternately, this acknowledgment may appear in the software itself,
  29          *    if and wherever such third-party acknowledgments normally appear.
  30          *
  31          * 4. The names "Apache" and "Apache Software Foundation" and
  32          *    "Apache Lucene" must not be used to endorse or promote products
  33          *    derived from this software without prior written permission. For
  34          *    written permission, please contact apache@apache.org.
  35          *
  36          * 5. Products derived from this software may not be called "Apache",
  37          *    "Apache Lucene", nor may "Apache" appear in their name, without
  38          *    prior written permission of the Apache Software Foundation.
  39          *
  40          * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  41          * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  42          * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  43          * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  44          * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45          * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  46          * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  47          * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  48          * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  49          * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  50          * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51          * SUCH DAMAGE.
  52          * ====================================================================
  53          *
  54          * This software consists of voluntary contributions made by many
  55          * individuals on behalf of the Apache Software Foundation.  For more
  56          * information on the Apache Software Foundation, please see
  57          * <http://www.apache.org/>.
  58          */
  59
  60         sealed  class SegmentInfos : ArrayList
  61         {
  62                 public int counter = 0;                   // used to name new segments
  63
  64                 public SegmentInfo Info(int i)
  65                 {
  66                         return (SegmentInfo)this[i];
  67                 }
  68
  69                 public void Read(Directory directory)
  70                 {
  71                         InputStream input = directory.OpenFile("segments");
  72                         try
  73                         {
  74                                 counter = input.ReadInt();                // read counter
  75                                 for (int i = input.ReadInt(); i > 0; i--)
  76                                 { // read segmentInfos
  77                                         SegmentInfo si =
  78                                                 new SegmentInfo(input.ReadString(), input.ReadInt(), directory);
  79                                         Add(si);
  80                                 }
  81                         }
  82                         finally
  83                         {
  84                                 input.Close();
  85                         }
  86                 }
  87
  88                 public void Write(Directory directory)
  89                 {
  90                         OutputStream output = directory.CreateFile("segments.new");
  91                         try
  92                         {
  93                                 output.WriteInt(counter);                         // write counter
  94                                 output.WriteInt(Count);                   // write infos
  95                                 for (int i = 0; i < Count; i++)
  96                                 {
  97                                         SegmentInfo si = Info(i);
  98                                         output.WriteString(si.name);
  99                                         output.WriteInt(si.docCount);
 100                                 }
 101                         }
 102                         finally
 103                         {
 104                                 output.Close();
 105                         }
 106
 107                         // install new segment info
 108                         directory.RenameFile("segments.new", "segments");
 109                 }
 110         }
 111 }