FilePart


1   // Copyright (C) 1999-2001 by Jason Hunter <jhunter_AT_acm_DOT_org>.
2   // All rights reserved.  Use of this class is limited.
3   // Please see the LICENSE for more information.
4   
5   package com.oreilly.servlet.multipart;
6   
7   import java.io.File  ;
8   import java.io.InputStream  ;
9   import java.io.OutputStream  ;
10  import java.io.BufferedOutputStream  ;
11  import java.io.FileOutputStream  ;
12  import java.io.IOException  ;
13  import javax.servlet.ServletInputStream  ;
14  
15  /**
16   * A <code>FilePart</code> is an upload part which represents a 
17   * <code>INPUT TYPE="file"</code> form parameter.  Note that because file 
18   * upload data arrives via a single InputStream, each FilePart's contents
19   * must be read before moving onto the next part.  Don't try to store a
20   * FilePart object for later processing because by then their content will
21   * have been passed by.
22   * 
23   * @author Geoff Soutter
24   * @version 1.2, 2001/01/22, getFilePath() addition thanks to Stefan Eissing
25   * @version 1.1, 2000/11/26, writeTo() bug fix thanks to Mike Shivas
26   * @version 1.0, 2000/10/27, initial revision
27   */
28  public class FilePart extends Part {
29    
30    /** "file system" name of the file  */
31    private String   fileName;     
32    
33    /** path of the file as sent in the request, if given */
34    private String   filePath;
35  
36    /** content type of the file */
37    private String   contentType;   
38    
39    /** input stream containing file data */
40    private PartInputStream partInput;  
41      
42    /** file rename policy */
43    private FileRenamePolicy policy;
44  
45    /**
46     * Construct a file part; this is called by the parser.
47     * 
48     * @param name the name of the parameter.
49     * @param in the servlet input stream to read the file from.
50     * @param boundary the MIME boundary that delimits the end of file.
51     * @param contentType the content type of the file provided in the 
52     * MIME header.
53     * @param fileName the file system name of the file provided in the 
54     * MIME header.
55     * @param filePath the file system path of the file provided in the
56     * MIME header (as specified in disposition info).
57     * 
58     * @exception IOException if an input or output exception has occurred.
59     */
60    FilePart(String   name, ServletInputStream   in, String   boundary,
61             String   contentType, String   fileName, String   filePath)
62                                                     throws IOException   {
63      super(name);
64      this.fileName = fileName;
65      this.filePath = filePath;
66      this.contentType = contentType;
67      partInput = new PartInputStream(in, boundary);
68    }
69  
70    /**
71     * Puts in place the specified policy for handling file name collisions.
72     */
73    public void setRenamePolicy(FileRenamePolicy policy) {
74      this.policy = policy;
75    }
76    
77    /**
78     * Returns the name that the file was stored with on the remote system, 
79     * or <code>null</code> if the user didn't enter a file to be uploaded. 
80     * Note: this is not the same as the name of the form parameter used to 
81     * transmit the file; that is available from the <code>getName</code>
82     * method.  Further note: if file rename logic is in effect, the file
83     * name can change during the writeTo() method when there's a collision
84     * with another file of the same name in the same directory.  If this
85     * matters to you, be sure to pay attention to when you call the method.
86     * 
87     * @return name of file uploaded or <code>null</code>.
88     * 
89     * @see Part#getName()
90     */
91    public String   getFileName() {
92      return fileName;
93    }
94  
95    /**
96     * Returns the full path and name of the file on the remote system,
97     * or <code>null</code> if the user didn't enter a file to be uploaded.
98     * If path information was not supplied by the remote system, this method
99     * will return the same as <code>getFileName()</code>.
100    *
101    * @return path of file uploaded or <code>null</code>.
102    *
103    * @see Part#getName()
104    */
105   public String   getFilePath() {
106     return filePath;
107   }
108 
109   /** 
110    * Returns the content type of the file data contained within.
111    * 
112    * @return content type of the file data.
113    */
114   public String   getContentType() {
115     return contentType;
116   }
117   
118   /**
119    * Returns an input stream which contains the contents of the
120    * file supplied. If the user didn't enter a file to upload
121    * there will be <code>0</code> bytes in the input stream.
122    * It's important to read the contents of the InputStream 
123    * immediately and in full before proceeding to process the 
124    * next part.  The contents will otherwise be lost on moving
125    * to the next part.
126    * 
127    * @return an input stream containing contents of file.
128    */
129   public InputStream   getInputStream() {
130     return partInput;
131   }
132 
133   /**
134    * Write this file part to a file or directory. If the user 
135    * supplied a file, we write it to that file, and if they supplied
136    * a directory, we write it to that directory with the filename
137    * that accompanied it. If this part doesn't contain a file this
138    * method does nothing.
139    *
140    * @return number of bytes written
141    * @exception IOException if an input or output exception has occurred.
142    */
143   public long writeTo(File   fileOrDirectory) throws IOException   {
144     long written = 0;
145     
146     OutputStream   fileOut = null;
147     try {
148       // Only do something if this part contains a file
149       if (fileName != null) {
150         // Check if user supplied directory
151         File   file;
152         if (fileOrDirectory.isDirectory()) {
153           // Write it to that dir the user supplied, 
154           // with the filename it arrived with
155           file = new File  (fileOrDirectory, fileName);
156         }
157         else {
158           // Write it to the file the user supplied,
159           // ignoring the filename it arrived with
160           file = fileOrDirectory;
161         }
162         if (policy != null) {
163           file = policy.rename(file);
164           fileName = file.getName();
165         }
166         fileOut = new BufferedOutputStream  (new FileOutputStream  (file));
167         written = write(fileOut);
168       }
169     }
170     finally {
171       if (fileOut != null) fileOut.close();
172     }
173     return written;
174   }
175 
176   /**
177    * Write this file part to the given output stream. If this part doesn't 
178    * contain a file this method does nothing.
179    *
180    * @return number of bytes written.
181    * @exception IOException if an input or output exception has occurred.
182    */
183   public long writeTo(OutputStream   out) throws IOException   {
184     long size=0;
185     // Only do something if this part contains a file
186     if (fileName != null) {
187       // Write it out
188       size = write( out );
189     }
190     return size;
191   }
192 
193   /**
194    * Internal method to write this file part; doesn't check to see
195    * if it has contents first.
196    *
197    * @return number of bytes written.
198    * @exception IOException if an input or output exception has occurred.
199    */
200   long write(OutputStream   out) throws IOException   {
201     // decode macbinary if this was sent
202     if (contentType.equals("application/x-macbinary")) {
203       out = new MacBinaryDecoderOutputStream(out);
204     }
205     long size=0;
206     int read;
207     byte[] buf = new byte[8 * 1024];
208     while((read = partInput.read(buf)) != -1) {
209       out.write(buf, 0, read);
210       size += read;
211     }
212     return size;
213   }
214   
215   /**
216    * Returns <code>true</code> to indicate this part is a file.
217    * 
218    * @return true.
219    */
220   public boolean isFile() {
221     return true;
222   }
223 }
224
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