I want to do some simple sums with some currency values expressed in BigDecimal type.
BigDecimal test = new BigDecimal(0);
System.out.println(test);
test.add(new BigDecimal(30));
System.out.println(test);
test.add(new BigDecimal(45));
System.out.println(test);
Obviously I do not understand well the BigDecimal arithmetics, see output behind.
Test
0
0
0
Can anyone help me out?
BigInteger is immutable, just like Strings. That means we cannot change it's content once the object is created, but we can re-assign it.
BigInteger sum = test.add(new BigInteger(30));
System.out.println(sum);
.add() will return a new Object
Using Java8 lambdas
List<BigDecimal> items = Arrays.asList(a, b, c, .....);
items.stream().filter(Objects::nonNull).reduce(BigDecimal.ZERO, BigDecimal::add);
This covers cases where the some or all of the objects in the list is null.