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1   /* CompositeFileInputStream
2   *
3   * $Id: CompositeFileInputStream.java 4647 2006-09-22 18:39:39Z paul_jack $
4   *
5   * Created on May 18, 2004
6   *
7   * Copyright (C) 2004 Internet Archive.
8   *
9   * This file is part of the Heritrix web crawler (crawler.archive.org).
10  *
11  * Heritrix is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU Lesser Public License as published by
13  * the Free Software Foundation; either version 2.1 of the License, or
14  * any later version.
15  *
16  * Heritrix is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU Lesser Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser Public License
22  * along with Heritrix; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
24  */
25  package org.archive.io;
26  
27  import java.io.File;
28  import java.io.FileInputStream;
29  import java.io.FilterInputStream;
30  import java.io.IOException;
31  import java.util.Iterator;
32  import java.util.List;
33  
34  
35  /***
36   * @author gojomo
37   */
38  public class CompositeFileInputStream extends FilterInputStream{
39      Iterator<File> filenames;
40  
41      /* (non-Javadoc)
42       * @see java.io.InputStream#read()
43       */
44      public int read() throws IOException {
45          int c = super.read();
46          if( c == -1 && filenames.hasNext() ) {
47              cueStream();
48              return read();
49          }
50          return c;
51      }
52      /* (non-Javadoc)
53       * @see java.io.InputStream#read(byte[], int, int)
54       */
55      public int read(byte[] b, int off, int len) throws IOException {
56          int c = super.read(b, off, len);
57          if( c == -1 && filenames.hasNext() ) {
58              cueStream();
59              return read(b,off,len);
60          }
61          return c;
62      }
63      /* (non-Javadoc)
64       * @see java.io.InputStream#read(byte[])
65       */
66      public int read(byte[] b) throws IOException {
67          int c = super.read(b);
68          if( c == -1 && filenames.hasNext() ) {
69              cueStream();
70              return read(b);
71          }
72          return c;
73      }
74  
75      /* (non-Javadoc)
76       * @see java.io.InputStream#skip(long)
77       */
78      public long skip(long n) throws IOException {
79          long s = super.skip(n);
80          if( s<n && filenames.hasNext() ) {
81              cueStream();
82              return s + skip(n-s);
83          }
84          return s;
85      }
86  
87      /***
88       * @param files
89       * @throws IOException
90       */
91      public CompositeFileInputStream(List<File> files) throws IOException {
92          super(null);
93          filenames = files.iterator();
94          cueStream();
95      }
96  
97      private void cueStream() throws IOException {
98          if(filenames.hasNext()) {
99              this.in = new FileInputStream(filenames.next());
100         }
101     }
102 
103 }