import java.io.*;
public class FileList {

 String path = "C://";
 public void FileListMethod(){
  File file = new File(path);
  String[] str = file.list(new FileNameFilterMethod());
  for(int i=0;i<str.length;i++){
   System.out.println(str[i]);
  }
 }
 public static void main(String[] args) {
  // TODO Auto-generated method stub

  FileList flist = new FileList();
  flist.FileListMethod();
  
   }

} 

import java.io.*;

public class FileNameFilterMethod implements FilenameFilter{

// private String filter;
// public void FileNameFilterMethod(String filter){
//  this.filter=filter;
// }

 public boolean accept(File dir, String name) {
  // TODO Auto-generated method stub
  if(name.length()==10)
      return true;
  else
   return false;
 }

}