sign « Number Format « Java Data Type Q&A

1. Format negative amount of USD with a minus sign, not brackets (Java)

How do I get NumberFormat.getCurrencyInstance() to print negative USD currency values with a minus sign?

2. Pound sign from number format?

NumberFormat nf = NumberFormat.getCurrencyInstance(Locale.UK);
BigDecimal b = new BigDecimal("10");
System.out.println (String.format("Data %s", nf.format(b.doubleValue())));
This outputs Data ?10 How can I get the pound sign, for US if I change locale it outputs dollar sign.

3. Format a number with leading sign

How do I format in Java a number with its leading sign? Negative numbers are correctly displayed with leading -, but obviously positive numbers are not displayed with +. How to do that ...