I'm trying to add a value to a variable of type BigDecimal, however regardless of the calculation it results in 0.
Sample code:
BigDecimal valorTotal = new BigDecimal(0);
public void adicionarVenda(int idProduto, int quantidade) {
BigDecimal newQtd = new BigDecimal(quantidade);
BigDecimal newQtd2 = newQtd.multiply(preco);
valorTotal.add(newQtd2);
System.out.println(valorTotal);
}
The problem is that you can not change the value BigDecimal , it is immutable. So you should create a new BigDecimal to store the result, which should be the goal of your valorTotal variable.
Example:
Assuming that preco is 10 and that quantidade is also 10:
BigDecimal preco = new BigDecimal(10);
And modifying your method to:
BigDecimal newQtd = new BigDecimal(quantidade);
BigDecimal newQtd2 = newQtd.multiply(preco);
valorTotal = valorTotal.add(newQtd2); // <<
System.out.println(valorTotal.toString());
The result is 100. Version on ideone: link .
This happens because the add only returns a BigDecimal.
To fix, you only need to assign the sum to the total value:
valorTotal = valorTotal.Add(newQtd2);