NumberFormat Class in Java

NumberFormat is an abstract class used to format numbers into locale-specific strings and to parse formatted strings back into numbers. It supports multiple locales, making it ideal for internationalized Java applications. It:

• Displays numbers in a clear, user-friendly, and locale-aware format
• Easily formats currency and percentage values
• Simplifies handling of internationalization (i18n) requirements
• Safely parses formatted numeric strings back into numbers

Commonly Used Factory Methods

Since NumberFormat is abstract, instances are created using its factory methods:

Example: Formatting a Number

import java.text.NumberFormat;

public class GFG {
    public static void main(String[] args) {
        NumberFormat nf = NumberFormat.getInstance();
        System.out.println(nf.format(1234567.89));
    }
}

1,234,567.89

Explanation:

• NumberFormat.getInstance() returns a NumberFormat object for the system’s default locale.
• nf.format(1234567.89) converts the numeric value into a locale-specific formatted string.
• The output includes appropriate grouping separators (such as commas) based on the locale.

Note: Output may vary by locale.

Parsing Numbers Using NumberFormat

The parse() method converts formatted strings back into numeric values.

import java.text.NumberFormat;

public class GFG {
    public static void main(String[] args) throws Exception {
        NumberFormat nf = NumberFormat.getInstance();
        Number num = nf.parse("1,234");
        System.out.println(num);
    }
}

1234

Explanation:

• NumberFormat.getInstance() creates a formatter configured for the default locale.
• nf.parse("1,234") converts the formatted string back into a numeric Number object.
• The parsed result removes locale-specific symbols and prints the actual numeric value (1234).

NumberFormat vs DecimalFormat