delete directory / Folder

public static void deleteDirectory( File dir )
{

    if ( dir.isDirectory() )
    {
        String [] children = dir.list();
        for ( int i = 0 ; i < children.length ; i ++ )
        {
         File child =    new File( dir , children[i] );
         if(child.isDirectory()){
             deleteDirectory( child );
             child.delete();
         }else{
             child.delete();

         }
        }
        dir.delete();
    }
}