Re: Out of memory with file streams

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Mon, 17 Mar 2008 09:03:03 -0400
Message-ID:
<7q-dnRaLXZCa8UPanZ2dnUVZ_ournZ2d@comcast.com>
Hendrik Maryns wrote:
....

So I am on the lookout for a memory leak, however, I can2"t find it. The
preprocessing method basically does the following (suppose the inFile
and the treeFile are given Files):

final BufferedReader corpus = new BufferedReader(new FileReader(inFile));
final ObjectOutputStream treeOut = new ObjectOutputStream(new
BufferedOutputStream(new FileOutputStream(treeFile)));
final int nbTrees = TreebankConverter.parseNegraTrees(corpus, treeOut);
try {
    treeOut.close();
} catch (final IOException e) {
    // if it cannot be closed, it wasn2"t open
}
try {
    corpus.close();
} catch (final IOException e) {
    // if it cannot be closed, it wasn2"t open
}
...
This is also done one by one:

TreebankConverter.skipHeader(corpus);
String bosLine;
while ((bosLine = corpus.readLine()) != null) {
 final StringTokenizer tokens = new StringTokenizer(bosLine);
 final String treeIdLine = tokens.nextToken();
 if (!treeIdLine.equals("%%")) {
  final String treeId = tokens.nextToken();
  final NodeSet forest = parseSentenceNodes(corpus);
  final Node root = forest.toTree();
  final BinaryNode binRoot = root.toBinaryTree(new ArrayList<Node>(), 0);
  final BinaryTree binTree = new BinaryTree(binRoot, treeId);
  treeOut.writeObject(binTree);
 }
}

I see no reason in the above code why the GC wouldn2"t discard the trees
that have been constructed before.

So the only place for memory problems I see here is the file access.
However, as I grasp from the Javadocs, both FileReader and
FileOutputStream are, indeed streams, that do not have to remember what
came before. Is the buffering the problem, maybe?


When incomplete code is posted with a question, the answer is pretty much
always in the code not posted. Check through the code you left out of your
post for packratted references.

<http://mindprod.com/jgloss/sscce.html>
<http://mindprod.com/jgloss/packratting.html>

--
Lew

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