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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    * 
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.vfs;
18  
19  import java.io.IOException;
20  import java.io.InputStream;
21  import java.io.OutputStream;
22  
23  /***
24   * Utility methods for dealng with FileObjects.
25   *
26   * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
27   * @version $Revision: 480428 $ $Date: 2006-11-29 07:15:24 +0100 (Mi, 29 Nov 2006) $
28   */
29  public class FileUtil
30  {
31      private FileUtil()
32      {
33      }
34  
35      /***
36       * Returns the content of a file, as a byte array.
37       *
38       * @param file The file to get the content of.
39       */
40      public static byte[] getContent(final FileObject file)
41          throws IOException
42      {
43          final FileContent content = file.getContent();
44          final int size = (int) content.getSize();
45          final byte[] buf = new byte[size];
46  
47          final InputStream in = content.getInputStream();
48          try
49          {
50              int read = 0;
51              for (int pos = 0; pos < size && read >= 0; pos += read)
52              {
53                  read = in.read(buf, pos, size - pos);
54              }
55          }
56          finally
57          {
58              in.close();
59          }
60  
61          return buf;
62      }
63  
64      /***
65       * Writes the content of a file to an OutputStream.
66       */
67      public static void writeContent(final FileObject file,
68                                      final OutputStream outstr)
69          throws IOException
70      {
71          final InputStream instr = file.getContent().getInputStream();
72          try
73          {
74              final byte[] buffer = new byte[1024];
75              while (true)
76              {
77                  final int nread = instr.read(buffer);
78                  if (nread < 0)
79                  {
80                      break;
81                  }
82                  outstr.write(buffer, 0, nread);
83              }
84          }
85          finally
86          {
87              instr.close();
88          }
89      }
90  
91      /***
92       * Copies the content from a source file to a destination file.
93       */
94      public static void copyContent(final FileObject srcFile,
95                                     final FileObject destFile)
96          throws IOException
97      {
98          // Create the output stream via getContent(), to pick up the
99          // validation it does
100         final OutputStream outstr = destFile.getContent().getOutputStream();
101         try
102         {
103             writeContent(srcFile, outstr);
104         }
105         finally
106         {
107             outstr.close();
108         }
109     }
110 
111 }