moparisthebest/poi
1
0
Fork 0
Code Issues Pull Requests Releases 1 Wiki Activity

Tweak NPOIFS constructors so that if you have a FileChannel, you can pass it in, but that the File based one will tidy up after itself in the event of errors

Browse Source 
git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1054033 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Nick Burch 2010-12-31 00:46:00 +00:00
parent c82f06605e
commit 2d9837bd90
1 changed files with 64 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

73
src/java/org/apache/poi/poifs/filesystem/NPOIFSFileSystem.java
View File

@ -107,7 +107,7 @@ public class NPOIFSFileSystem extends BlockStore
/**
* Creates a POIFSFileSystem from a <tt>File</tt>. This uses less memory than
* creating from an <tt>InputStream</tt>.
* creating from an <tt>InputStream</tt>. The File will be opened read-only
*
* Note that with this constructor, you will need to call {@link #close()}
* when you're done to have the underlying file closed, as the file is
@ -119,22 +119,71 @@ public class NPOIFSFileSystem extends BlockStore
*/
public NPOIFSFileSystem(File file)
throws IOException
{
this(file, true);
}
/**
* Creates a POIFSFileSystem from a <tt>File</tt>. This uses less memory than
* creating from an <tt>InputStream</tt>.
*
* Note that with this constructor, you will need to call {@link #close()}
* when you're done to have the underlying file closed, as the file is
* kept open during normal operation to read the data out.
*
* @param file the File from which to read the data
*
* @exception IOException on errors reading, or on invalid data
*/
public NPOIFSFileSystem(File file, boolean readOnly)
throws IOException
{
this(
(new RandomAccessFile(file, readOnly? "r" : "rw")).getChannel(),
true
);
}
/**
* Creates a POIFSFileSystem from an open <tt>FileChannel</tt>. This uses
* less memory than creating from an <tt>InputStream</tt>.
*
* Note that with this constructor, you will need to call {@link #close()}
* when you're done to have the underlying Channel closed, as the channel is
* kept open during normal operation to read the data out.
*
* @param channel the FileChannel from which to read the data
*
* @exception IOException on errors reading, or on invalid data
*/
public NPOIFSFileSystem(FileChannel channel)
throws IOException
{
this(channel, false);
}
private NPOIFSFileSystem(FileChannel channel, boolean closeChannelOnError)
throws IOException
{
this();
// Open the underlying channel
FileChannel channel = (new RandomAccessFile(file, "r")).getChannel();
try {
// Get the header
ByteBuffer headerBuffer = ByteBuffer.allocate(POIFSConstants.SMALLER_BIG_BLOCK_SIZE);
IOUtils.readFully(channel, headerBuffer);
// Get the header
ByteBuffer headerBuffer = ByteBuffer.allocate(POIFSConstants.SMALLER_BIG_BLOCK_SIZE);
IOUtils.readFully(channel, headerBuffer);
// Have the header processed
_header = new HeaderBlock(headerBuffer);
// Have the header processed
_header = new HeaderBlock(headerBuffer);
// Now process the various entries
_data = new FileBackedDataSource(channel);
readCoreContents();
// Now process the various entries
_data = new FileBackedDataSource(channel);
readCoreContents();
} catch(IOException e) {
if(closeChannelOnError) {
channel.close();
}
throw e;
}
}
/**