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Java > Open Source Codes > org > jahia > tools > files > FileDownload


1 package org.jahia.tools.files;
2
3
4 /*
5  * FileDownload
6  * Copyright (c) 2000 xo3.com All rights reserved.
7  *
8  */
9
10
11 import java.io.*;
12 import java.util.*;
13 import javax.servlet.*;
14 import javax.servlet.http.*;
15
16 import com.oreilly.servlet.*;
17
18 /**
19  * Class FileDownload.
20  * Class to handle filedownload
21  *
22  * @author Khue ng <a HREF="mailto:khue@xo3.com">khue@xo3.com</a>
23  * @version 1.0
24  */
25 public class FileDownload {
26
27
28    private HttpServletRequest m_Req;
29    private HttpServletResponse m_Res;
30
31     private String JavaDoc m_FileRealName = "";
32     private String JavaDoc m_FileStorageFullPath = "";
33     private String JavaDoc m_FileContentType = "";
34
35    private int m_BufferSize = 4096;
36    private byte[] m_WriteBuffer = new byte[m_BufferSize];
37
38
39     /**
40      * Constructor
41      *
42      * @param req the HttpServletRequest object
43      * @param res the HttpServletResponse object
44      * @param fileRealName the real name of the file
45      * @param fileStorageFullPath the storage name of the file
46      * @param fileContentType the Content Type of the file
47      */
48      public FileDownload(
49                                 HttpServletRequest req,
50                                 HttpServletResponse res,
51                                 String JavaDoc fileRealName,
52                                 String JavaDoc fileStorageFullPath,
53                                 String JavaDoc fileContentType){
54         
55         m_Req = req;
56         m_Res = res;
57         m_FileRealName = fileRealName;
58         m_FileStorageFullPath = fileStorageFullPath;
59         m_FileContentType = fileContentType;
60      
61      }
62
63
64     /**
65      * Method writeFileContentToResponse<br>
66      * Write file content to the client
67      *
68      * @exception IOException
69      */
70     public void writeFileContentToResponse() throws IOException {
71         
72         toConsole("FileDownload, fullRealpath is " + m_FileStorageFullPath);
73         File theFile = new File(m_FileStorageFullPath);
74         if ( theFile.exists() && theFile.isFile() && theFile.canRead() ){
75  
76             // Write Header
77 m_Res.setContentLength((int)theFile.length());
78             m_Res.setContentType(m_FileContentType);
79             m_Res.setHeader("Content-Disposition","attachment; filename=\"" + m_FileRealName + "\"");
80             m_Res.setDateHeader("Date", new Date().getTime());
81             m_Res.setDateHeader("Expires", new Date().getTime());
82             m_Res.setIntHeader("Age",0);
83             m_Res.setIntHeader("Retry-After",60);
84             m_Res.setHeader("Pragma","no-cache");
85             m_Res.setHeader("Connection","Keep-Alive");
86             
87             try {
88                 copyStream(new FileInputStream(m_FileStorageFullPath), m_Res.getOutputStream());
89             } catch (IOException ioe) {
90                 toConsole("FileDownload :: Error writing file to response" + ioe.getMessage());
91                 throw new IOException("FileDownload::writeFileContentToResponse error while writing to client");
92             }
93         } else {
94             toConsole("FileDownload :: checkFile, file denoted by " + m_FileStorageFullPath + " doesn't exist or cannot be read");
95             throw new IOException("FileDownload::writeFileContentToResponse error while trying to open file");
96         }
97         
98     }
99
100
101     /**
102     * Method copyStream<br>
103     *
104     * @param ins An InputStream.
105     * @param outs An OutputStream.
106     * @exception IOException.
107     */
108    private void copyStream(InputStream ins,
109                             OutputStream outs)
110        throws IOException
111    {
112        BufferedInputStream bis =
113            new BufferedInputStream(ins, m_BufferSize);
114        BufferedOutputStream bos =
115            new BufferedOutputStream(outs, m_BufferSize);
116        int bufread;
117         while((bufread = bis.read(m_WriteBuffer)) != -1)
118            bos.write(m_WriteBuffer,0,bufread);
119        bos.flush(); bos.close();
120        bis.close();
121    }
122
123
124
125     /** Method toConsole
126      * For debugging purpose
127      *
128      * @param msg any String message to write to the console
129      */
130     public void toConsole(String JavaDoc msg) {
131         System.out.println(msg);
132     }
133     
134 }
135
136
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