class Main{
  public static void main(String[] a){
    String s = "0400";
    int i = Integer.parseInt(s);
    System.out.println("From: \""+s+"\"; to: "+i);
 
    int n = 0400;
    String asOctal = Integer.toString(n, 8);   // Convert from base-8 to base-10
    int asDecimal = Integer.valueOf(asOctal);  // Base-10 by default
    System.out.println("From: "+n+" (base-8 integer); to: \""+asOctal+"\" (base-10 as String) or "+asDecimal+" (base-10 as integer)");
  }
}

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