An easy way to output currency in Java is to use the built-inNumberFormat class. This lets you format a number like1000.2399 for output as$1,000.24.

NumberFormat rounds to two decimals, adds necessary commas, and includes a$ in front.

To use NumberFormat, import the class at the top of your program:

importjava.text.NumberFormat;

Next, create the NumberFormat object and assign it to a variableformatter:

NumberFormatformatter=NumberFormat.getCurrencyInstance();

Finally, use theformatter object to invoke theformat() method on the amount to be formatted:

doubleamt=1000.2399;StringamtFormatted=formatter.format(amt);

Note that the result is aString value.

Here is a full program example:

importjava.text.NumberFormat;publicclassNumberFormatExample{publicstaticvoidmain(String[]args){NumberFormatformatter=NumberFormat.getCurrencyInstance();doubleamt=1000.2399;StringamtFormatted=formatter.format(amt);System.out.println("original:    "+amt);System.out.println("formatted:   "+amtFormatted);}}

Here is the output:

original:    1000.2399formatted:   $1,000.24

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