Sorting files from a directory by their names

Question

I had been asked a question in an interview,I could not understand what exactly to do ,However the question and my solution I am presenting here,Please comment on my solution and if it is not right the givw exact solution.
Q) A directory has number of SQL files that are used to build the database as part of release cycle.The file names has the number that indicates the sql statement inside the fils needs to be executed.For instance if following files are found
1_create_table.sql ,
11_assign_privileges.sql,
12_07_ insert_static_data.sql,
2_create_index.sql
correct execution order would be
1_create_table.sql ,
2_create_index.sql,
11_assign_privileges.sql,
12_07_ insert_static_data.sql,
Write a set of production quality OO Classes that can provide files names in the order of execution.Progarm should take base directory as input.No need to provide code for sql cript execution.
Solution: I understood that we have a directory in which these 4 files resides,We write a java code and pick up the files according to theier name in ascending order.
I did it by string tokenizer but again thought using comparator might be good solution.this is my code
import java.util.Arrays;
import java.util.Comparator;
import java.io.*;
public class SQLDemo {
public static void main(String[] args) {
//... Create comparators for sorting.
Comparator byDirThenAlpha = new DirAlphaComparator();
// Create a File object for user directory.
File dir = new File(System.getProperty("user.home"));
File[] children = dir.listFiles();
System.out.println("Files by directory, then alphabetical");
Arrays.sort(children, byDirThenAlpha);
printFileNames(children);
private static void printFileNames(File[] f) {
for (int i = 0; i < f.length; i++) {
System.out.println(" " + f.getName());
// DirAlphaComparator to sort directories before files, then alphabetically.
class DirAlphaComparator implements Comparator {
// Comparator interface requires defining compare method.
public int compare(File filea, File fileb) {
//... Sort directories before files,
// otherwise alphabetical ignoring case.
if (filea.isDirectory() && !fileb.isDirectory()) {
return -1;
} else if (!filea.isDirectory() && fileb.isDirectory()) {
return 1;
} else {
return filea.getName().compareToIgnoreCase(fileb.getName());
public int compare(Object o1, Object o2) {
return 0;
Is this right way ,If other ways are possible the let me know.

Answer 1

sumit7nov wrote:
yes you are right,they want to sort it by numbers .Do you have nay idea how can we write the code for this?Please stay in one thread ... continuing both threads wastes everyones time, because we don't know if you've got an answer already.