private StringBuffer pad(StringBuffer toAppendTo, int initLength) {
        int numLength = toAppendTo.length() - initLength;
        int padLength = minimumLength - numLength;
        if (padLength > 0) {
            toAppendTo.insert(initLength, " ".repeat(padLength));
        }
        return toAppendTo;
    }
Creates a PaddingDecimalFormat using the given pattern and minimum minimumLength and the
symbols for the default locale.
tools/src/main/java/org/apache/kafka/tools/automq/perf/PaddingDecimalFormat.java