Help with recursion and files

[Martin Swift]

I am trying to read dirs whitin dirs with the following attached funcion. The second time I call the function no subdirs are found. If someone have any suggestions pleas help me.
Thank you

public void buildStructure(File filename, FileObject parent)
{
this.parent = parent;
this.workDir = filename;
FileFilter fileFilter = new FileFilter()
{
         /*return dirs in workDir*/
 public boolean accept(File file)
  {
    return file.isDirectory();
  }};
/*Check if there is any subdirs in dir <filename>, using filter*/
File[] subDirs = workDir.listFiles(fileFilter);
/*Class that hold info about dirs*/
                FileObject fob = new FileObjectImpl(workDir, parent);
if (subDirs == null)
{
System.out.println("Subdirs is null");
}
else
{
System.out.println("subDirs length " + subDirs.length);
for (int i = 0; i < subDirs.length; i++)
{
System.out.println("addsub dir " + subDirs[i]);
fob.addSubDir(new FileObjectImpl(subDirs[i],fob));
buildStructure(subDirs[i],fob);
}
}

}  

[Manfred Leonhardt]

Ztopher,
I think you are using to much extra coding that is not required. You only need a File object and should not keep sending in the result list. Also the fileFilter is not really required because you can just use the isFile function. If the item found is not a file then it must be a directory. With those changes your code looks like the following:

  
public void buildStructure( File fileName ) {
  ArrayList result = new ArrayList();
  File[] subDirs = fileName.listFiles();
  if (subDirs == null) {
    System.out.println("Subdirs is null");
  } else {
    System.out.println("subDirs length " + subDirs.length);
    for( int i = 0; i < subDirs.length; i++ ) {
      if( !subDirs[i].isFile() ) {
        System.out.println("addsub dir " + subDirs[i]);
        result.add( subDirs[i] );
        buildStructure( subDirs[i] );
      }
    }
  }
}  

Regards,
Manfred.

[Martin Swift]

Thank you !
Isn�t a good idea to pass the ArrayList as an argument to the function, like this?

  
public void buildStructure( File fileName, ArrayList result) 
{  
this.result = result;
System.out.println("Size of arrays "+ result.size());  
File[] subDirs = fileName.listFiles();  
if (subDirs == null) 
{    
System.out.println("Subdirs is null");  
} 
else 
{    
System.out.println("subDirs length " + subDirs.length);    
for( int i = 0; i < subDirs.length; i++ ) 
{      
if( !subDirs[i].isFile() ) 
{        
System.out.println("addsub dir " + subDirs[i].getName());        
result.add( subDirs[i] );        
buildStructure( subDirs[i],result);      
}    
}  
}
 
    }

In your version there is no point in using a collection or am I mistaken?
Cheers

[Dirk Schreckmann]

Moving this to the intermediate forum...