Java BigDecimal.add() is a method in the Java BigDecimal class that adds two BigDecimal values. It returns a new BigDecimal that represents the sum of the two operands, ensuring precision and immutability. Introduced in Java 2004 with Java 5, add() is commonly used in financial applications and any situation where high-precision arithmetic is required, such as in banking software or scientific calculations.

https://docs.oracle.com/javase/8/docs/api/java/math/BigDecimal.html