question: private String printDFormat ( long x ) { return printDFormat ( Long . toString ( x ) ) ; }
target:  Format method for the d conversion character and long argument. <p/> For d format, the flag character '-', means that the output should be left justified within the field.  The default is to pad with blanks on the left.  A '+' character means that the conversion will always begin with a sign (+ or -).  The blank flag character means that a non-negative input will be preceded with a blank.  If both a '+' and a ' ' are specified, the blank flag is ignored.  The '0' flag character implies that padding to the field width will be done with zeros instead of blanks. <p/> The field width is treated as the minimum number of characters to be printed.  The default is to add no padding.  Padding is with blanks by default. <p/> The precision, if set, is the minimum number of digits to appear.  Padding is with leading 0s.