DecimalFormat returns “ ? ” instead of “ - ” for negative Double input

Question

DecimalFormat returns ? symbol in place of - symbol, when the value given to it, is negative.

I am using ATOM with SCRIPT package and JDK12.0.2.

I can replace the " - "symbol with virtually any other symbol and the DecimalFormat will give a correct output. This is what makes this issue puzzling to me. I tried to look into locale issues, but did not manage to resolve the issue.

double nTest = -20.20;
System.out.println("simtest " + nTest + "C");

private static DecimalFormat desFor = new DecimalFormat("#0.0;-#0.0");
System.out.println("simtest " + desFor.format(-20.20) + "C");
System.out.println("simtest " + desFor.format(21.45) + "C");

private static DecimalFormat desForAny = new DecimalFormat("#0.0;*#0.0");
System.out.println("simtest " + desForAny.format(-20.20) + "C");

Results

simtest -20.2C

simtest ?20,2C  <=== expected  -20,2C

simtest 21,4C

simtest *20,2C

Answer 1

Try setting java.util.Locale

DecimalFormatSymbols symbols = DecimalFormatSymbols.getInstance(Locale.ENGLISH);
DecimalFormat desFor = new DecimalFormat("#0.0;-#0.0", symbols);