listFiles(new FilenameFilter()) and recursion

[Amy Hafer]

I have a servlet that takes HttpServlet requests (shapeName), finds those files in a directory on the server, and zips them up in a file for HttpServlet response. Problem is now I have files in subdirectories and I don't know how to recursively search through the subdirectories. The code is one class with an annonymous inner class, FilenameFilter. I could use suggestions on how best to do the recursion within the listFiles method as coded and add the files directly to the File[] theShapes. Hoping that creation of a new class to recurse through the directory is not necessary. Thanks!

 
try {
String[] paramValues = request.getParameterValues("box");
for(int k=0; k < paramValues.length; k++) 
    {final String shapeName = paramValues[k];
File[] theShapes = dir.listFiles(new FilenameFilter() {
       public boolean accept(File d, String name) { 
return ((name.endsWith(".shp") | | 
        name.endsWith(".shx") | |
        name.endsWith(".dbf")) && name.startsWith(shapeName + "."));
}
          });

 for (int i=0; i < theShapes.length; i++) { FileInputStream fis = new FileInputStream(theShapes[i]);
...THEN it goes on to create the zipfile and send as response...
}
catch ...

[This message has been edited by Amy Hafer (edited August 09, 2001).]

[James Swan]

Here is some code that will recurse down through directories.
Ok it has a hand coded "filter", but it still does the job.

import java.io.*;
import java.util.*;
public class ListFiles {
        
    public static void main(String[] args) {
        // eg java ListFiles c:\
        if (args.length > 0) {
            try {
                listFiles(new File(args[0]));
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    public static void listFiles(File dir) throws Exception {
        File[] files = dir.listFiles();
        for (int i = 0; i < files.length; i++) {
            String fileName = files[i].getName();
            // put in your filter here
            if (fileName.endsWith(".txt") | | fileName.endsWith(".class")) {
                if (files[i].isFile()) {
                    // do whatever you want with the file eg. add to Vector or similar
                    System.out.println(files[i].getPath());
                }
            }
            if (files[i].isDirectory()) {
                listFiles(files[i]);
            }
        }
    }
    
}

James.

[Amy Hafer]

Thanks James. I am trying it this way now. Do you have to do anything special with the file besides using the addElement(files(i)) method when you are putting the files in a Vector and sending it to a zip stream? For some reason, the file is not being found in the subdirectory (or maybe it is, it is just not being sent to the zip file).

public class ListFiles {
public static Vector listFilez(File tree, String shapeName) throws IOException {
Vector endAll = new Vector();
File[] files = tree.listFiles();
  for (int i = 0; i < files.length; i++) {
    String fileName = files[i].getName();
    if (files[i].isFile()) {
    if ((fileName.endsWith(".shp") | | fileName.endsWith(".dbf") | | fileName.endsWith(".shx")) && fileName.startsWith(shapeName + ".")) {
     endAll.addElement(files[i]);
    } 
     } 
    if (files[i].isDirectory()) {
listFilez(files[i],shapeName);
} 
   } 
return endAll;
} 
} 

[James Swan]

Hi Amy,
I am no expert on using the java.util.zip package but I would make these assumptions from reading the API:
(Also assumming you have contructed the appropriate ZipOutputStream)
1) you would iterate through your Vector retrieving each File object
2) for each file created construct a ZipEntry using the retrieved File object's getPath() method or (perhaps getAbsolutePath()) to make sure that the ZipEntry can find this file in the file system
3) add the ZipEntry to the ZipOutputStream via putNextEntry(ZipEntry e) method
Perhaps if you post your code for creating the zip file, we might be able to further determine what is going on.
James.

[Amy Hafer]

Hi James, you are probably right that it is the way I am constructing the zip file but ZipEntry is a string so I can't use getPath there. I am guessing the problem might be in this part of the code so for the sake of brevity (and clarity) here is the try statement where I am getting the HttpServletRequest called request and passing it to the ListFilez class and getting back the Vector (the list of files). Since it does work for the directory I originally start the search in but not for the subdirectory is definitely does sound like I need to use the getPath or getAbsolutePath method. Thank you for all your help so far!

try {

String[] paramValues = request.getParameterValues("box");
for(int k=0; k < paramValues.length; k++) {
    final String shapeName = paramValues[k];
    
Vector theShapes = ListFiles.listFilez(dir,shapeName); 
         Enumeration p = theShapes.elements();
  while(p.hasMoreElements()) {
File fred = (File)p.nextElement();                
                FileInputStream fis = new FileInputStream(fred);
BufferedInputStream bis = new BufferedInputStream(fis); 
ZipEntry entry = new ZipEntry(fred.getName());
zout.putNextEntry(entry);
int len=0;
while ((len=bis.read(b)) != -1) {
    zout.write(b,0,len);
    }
zout.flush();
zout.closeEntry();
fis.close();
    }
}
     
zout.close();  

**Actually I just realized that the problem is with the ListFiles class. The way it is written, the Vector is returned empty if the only file it is looking for is in the subdirectory. If it is looking for 2 files, one in the parent directory and one in the subdirectory, it will only return the file in the parent directory. So I am doing something wrong with how or where I created the Vector.
[This message has been edited by Amy Hafer (edited September 10, 2001).]