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ServletContext.getResource is not returning a directory under WebLogic 9.2

Posted on 2011-03-16

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Last Modified: 2012-06-27

Under Tomcat, we initialize some values based on the contents of a directory contained in an unexploded WAR file.
To do this, the code gets a URL by issuing a servletContext.getResource("/myFolder") where myFolder is in the war file at the appropriate place.
With the URL, we do a "getContent", which returns an object with class "javax.naming.directory.DirContext", which can be used to get all the files in the directory. All is fine in Tomcat.
When deployed under weblogic 9.2, the "getContent" returns a plain text object, which appears to be useless for our purposes.

Is there an appserver-independent way of getting a directory of files from an unexploded war file?

URL theFolderUrl = Z.context.getResource(tabCornerDir);
          if (theFolderUrl == null) return tabColorGifs;
          javax.naming.directory.DirContext jndd = (javax.naming.directory.DirContext)theFolderUrl.getContent();
//This last line produces a ClassCastException under weblogic
'weblogic.kernel.Default (self-tuning)' Exception = 
java.lang.ClassCastException: sun.net.www.content.text.PlainTextInputStream 
cannot be cast to javax.naming.directory.DirContext

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Question by:RogueCar

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1 Comment

Accepted Solution

by:RogueCar

RogueCar earned 0 total points

ID: 351672272011-03-18

Okay. With no answers forthcoming, I did some analysis and testing and discovered the following.
If the content type is plain text for a directory (as it is under weblogic), you can get the content of the url as an InputStream and read it.

I found that the InputStream returns a line (terminated by cr-lf) for each filename entry in the directory.

This turned out to be sufficient for my needs, so now the code parses the content in two ways:

1. as a directory under tomcat, and
2. as a plain text input stream under weblogic

I assume it is JRockit that is responsible for this rather odd content delivery, which could be considered a bug.

See the attached code snippet for details.

URLConnection uc = theFolderUrl.openConnection();
            Z.log.writeToLog(Z.log.DEBUG, "TD: resource type/length is:" + uc.getContentType() + "/" + uc.getContentLength());
            InputStream is = uc.getInputStream();
            InputStreamReader isr = new InputStreamReader(is, "UTF-8");
            BufferedReader br = new BufferedReader(isr);
            int fileCount = 0;
            while (true) {
              try {
                String fileName = br.readLine();
                fileCount++;
                //Z.log.writeToLog(Z.log.INFO, "TD: collected filename=" + fileName);
                if (fileName == null || fileCount > 500 ) break;
                theGifs.add(fileName);
              } catch(Exception e) {
                ErrorWriter.write(e, ErrorWriter.LOG);
                break;
              }
            }

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