java.math · java.base · since Java 1.1

BigDecimal

declaration

public class BigDecimal extends Number implements Comparable<BigDecimal>

Arbitrary-precision decimal arithmetic — the money type. Construct from String, divide with explicit scale and RoundingMode, compare with compareTo.

Key methods

`BigDecimal(String val) / static BigDecimal valueOf(double)`	Exact creation (the double CONSTRUCTOR copies binary error — avoid).
`BigDecimal add/subtract/multiply(BigDecimal)`	Exact arithmetic.
`BigDecimal divide(BigDecimal, int scale, RoundingMode)`	Division MUST specify rounding — 1/3 never terminates.
`BigDecimal setScale(int, RoundingMode)`	Normalize decimal places (money: 2, HALF_UP or HALF_EVEN).
`int compareTo(BigDecimal)`	Numeric comparison — equals() distinguishes 2.0 from 2.00!