How to Effectively Parse Double with Comma as Decimal Separator

Problem:

String values representing decimal numbers with commas as separators, like "1,234", can cause NumberFormatException when parsed using Double.valueOf().

Proposed Solution:

Replacing commas with periods using p = p.replaceAll(",", ".") is a valid approach, but there's a more robust method.

Java's NumberFormat for Decimal Parsing:

To handle decimals with locale-specific separators, Java provides NumberFormat. Consider the following code:

NumberFormat format = NumberFormat.getInstance(Locale.FRANCE);
Number number = format.parse("1,234");
double d = number.doubleValue();

Update for Multi-Language Applications:

In multilingual applications, locale-specific decimal separators are important. To support this, use NumberFormat.getInstance(Locale.getDefault()) to get the current locale's format.

Advantages of NumberFormat:

• Handles commas and locale-specific separators.
• Provides flexibility for various input formats.
• Ensures parsing and representation are consistent with the set locale.