Stephan van Hulst wrote:To further clarify what Paweł wrote, the value you are using to create the BigDecimal instance with is not actually -0.206, but the closest value that can be represented by the double datatype.
And this value is exactly -0.2059999999999999886757251488234032876789569854736328125.
There are 5 append methods in StringBuilder with one parameter that is a reference. The compiler doesn't know which of these you want to invoke when passing null as this could be any of them.
You can help the compiler by adding a type information to the call: