question: public MonetaryFormat decimalMark ( char decimalMark ) { checkArgument ( ! Character . isDigit ( decimalMark ) ) ; checkArgument ( decimalMark > 0 ) ; if ( decimalMark == this . decimalMark ) return this ; else return new MonetaryFormat ( negativeSign , positiveSign , zeroDigit , decimalMark , minDecimals , decimalGroups , shift , roundingMode , codes , codeSeparator , codePrefixed ) ; }
target:  Set character to use as the decimal mark. If the formatted value does not have any decimals, no decimal mark is used either.