Round a Double to 2 Decimal Places in Java (or N Places)
Learn how to round a double to 2 decimal places in Java with BigDecimal, Math.round(), String.format() and DecimalFormat, plus rounding modes and pitfalls.
Java printf() and String.format(): Format Specifier Guide
Java printf examples for %s, %d, %.2f, width, flags, dates and locales, plus String.format(), formatted() and fixes for common format exceptions.
Compact Number Formatting in Java: 1K, 1M and 1 Thousand
Compact number formatting in Java with CompactNumberFormat. Format 1000 as 1K or 1 thousand, control decimals and rounding, parse values and use locales.
Java Format Phone Number with Regex: (123) 456-7890
Java format phone number examples with regex groups and replaceFirst(), cleanup of typed input, a safe method with Optional, substring and E.164 storage.
Convert Float to String in Java with N Decimal Places
Convert float to String in Java with Float.toString(), String.format(“%.2f”) and DecimalFormat, plus locale, rounding, null and scientific notation.
Underscores in Numeric Literals in Java: Rules and Examples
Learn where underscores in numeric literals are allowed in Java, the invalid positions, grouping for hex and binary, and parsing 1_000 at runtime.