How to write nullable int in java?
You can use an Integer
, which is a reference type (class)in Java and therefore nullable.
Int32
(or int
) is a struct (value type) in C#. In contrast, Integer
in Java is a class which wraps an int
. Instances of reference types can be null
, which makes Integer
an legit option.
Nullable<T>
in .NET gives you similar options because it enables you to treat a value type like a nullable type. However, it's still different from Java's Integer
since it's implemented as a struct (value type) which can be compared to null
, but cannot actually hold a genuine null reference.
In Java, just use Integer
instead of int
. This is essentially a nullable int. I'm not too familiar with Struts, but using Integer
should allow you to omit the value.
Instead of using int
you can use Integer
(Integer javadoc) because it is a nullable Java class.