Read subdirectories and count files?

[jay lai]

Hello
i need some help on counting total files in each subdirectories . I already has a method reading the directories, but not sure how to count file for each subdirectories. I need to have the output like this. For example I read from c:\temp

result will like this:
c:\temp\one\ 3 (assume this sub-directory have 3 files)
c:\temp\one\two 10 (assume this sub-directory have 10 files)
c:\temp\one\two\three 4 (assume this sub-directory have 4 files)

You help is greatly appreciated.
Regards.

public static List getFiles( File aStartingDir ) 
{
    List result = new ArrayList();
 
    File[] filesAndDirs = aStartingDir.listFiles();
    List filesDirs = Arrays.asList(filesAndDirs);
    Iterator filesIter = filesDirs.iterator();
    File file = null;
    while ( filesIter.hasNext() ) {
      file = (File)filesIter.next();
      result.add(file); //always add, even if directory
      if (!file.isFile()) {
        //must be a directory
        //recursive call!
        List deeperList = getFileListing(file);
        result.addAll(deeperList);
      }
 
    }
    Collections.sort(result);
    return result;
  }
// this method return me the whole string of subdirectories including the file name c:\temp\one\file.txt, c:\temp\one\two\file2.txt...etc..
 

[Jim Yingst]

So what's this getFileListing() method you're calling? It looks like you're missing a method. And what happens when you run the code you have now? How are the results different from what you expect?

[jay lai]

Sorry for a late response, i was tight up with something else, and now I can revisit the problem.

the getFiles( File aStartingDir ) // giving me a list of directory including the directory and files name , so how do I do the count for how many files that are in the sub-directory under the parent directory
This is the out put of the getFiles method, How do I count each of the line and display the total files under each directory?
c:\temp\dir1\test1.txt
c:\temp\dir1\test2.txt
c:\temp\dir1\dir2\text3.txt
c:\temp\dir1\dir2\text4.txt
c:\temp\dir1\dir2\dir3\test5.txt

so the result should be like:
c:\temp\dir1\ 2 files
c:\temp\dir1\dir2\ 2 files
c:\temp\dir1\dir2\dir3\ 1 file

Any help or hints is greatly appreciated. Regards

[jay lai]

I am trying to count the totol files in each directory and print out,

Please help ! Thanks in advance

I do: java ListAllFiles c:\temp -----> it is giving NullPointerException?

 
import java.util.*;
import java.io.*;
 public class ListAllFiles
 {
public static void main(String[] args) 
{
 
           int test = 0;
   test = countFilesIn(args[0]);
           System.out.println("count " + test);
}

 
public static int countFilesIn( String aDirectory )
{
   File myFile = new File( aDirectory );
   boolean isDirectory = myFile.isDirectory(); // expect true
   File[] filesInDirectory = myFile.listFiles(); // now we have files in dir
   int fileCount = 0;
   for(int i = 0; i < filesInDirectory.length; i++ )
   {
  File oneFile = filesInDirectory[i];
  if ( oneFile.isDirectory() )
   {
 fileCount += countFilesIn( oneFile.getName() );
   }
  else
   {
 fileCount += 1;
   }
   }
   return fileCount;
}
 

 }
 

[Joe Ess]

It is always polite to share the exception stack trace as that contains the line number the exception occurs on.
One very useful debugging technique is to sprinkle System.out.println() statements throughout one's code. I always like to print out method calls and their parameters as well as important variables that I'm examining, like, say, if a file is a directory or not. Why don't you try this technique and share the results with us?

[Jim Yingst]

Note that the stack trace contains the line number of the exception, but that line number won't mean anything to us because we don't have your complete file. We can't tell what the line numbers mean. But if your stack trace starts off with

java.lang.NullPointerException
at ListAllFiles.foo(ListAllFiles.java:42)
        ...

that tells you to look at ListAllFiles.java, line 42. Tell us which line that is, and we might be able to help.

Also, I don't think this will explain your NullPointerException, but here's another problem:

fileCount += countFilesIn( oneFile.getName() );

When you call oneFile.getName(), you get only the name of the file, not the directory it's in. So the countFilesIn() methods won't be able to find the files, because it doesn't know where they are. I recommend you change the method to take a File parameter rather than a String - that way the File object still has all the info you need to find the file.