Java application Help?

public class DblArray{
  public static void main(String a[]){
  int i;
  double array[] = {12,9.5,4.5,6,4.2};
  System.out.println("Values from first to last:\n");
  for(i = 0; i < array.length; i++)
  System.out.print( array[i]+"  ");
  System.out.println();

  System.out.println("Values from last to first:\n");
  for(i = array.length-1; i>=0; i--)
  System.out.print( array[i]+"  ");
  System.out.println();
  System.out.println();
  bubble_srt(array, array.length);
  System.out.print("Values after the sort:\n");
  for(i = 0; i <array.length; i++)
  System.out.print(array[i]+"  ");
  System.out.println();
   }

  public static void bubble_srt( double a[], int n ){
  int i, j;
  double t=0;
  for(i = 0; i < n; i++){
  for(j = 1; j < (n-i); j++){
  if(a[j-1] > a[j]){
  t = a[j-1];
  a[j-1]=a[j];
  a[j]=t;
  }
  }
  }
  }
}