Set an optional field to a fixed value

1. What is the default value of optional?
2. How do you make a field optional in Java?
3. How to declare a optional parameter in c#?

What is the default value of optional?

The default value of any reference type member variable is null . The Optional type behaves as any other reference type.

How do you make a field optional in Java?

Use null to indicate optional data within the private scope of a class. Use Optional for getters that access the optional field. Do not use Optional in setters or constructors. Use Optional as a return type for any other business logic methods that have an optional result.

How to declare a optional parameter in c#?

Here for the [Optional] attribute is used to specify the optional parameter. Also, it should be noted that optional parameters should always be specified at the end of the parameters. For ex − OptionalMethodWithDefaultValue(int value1 = 5, int value2) will throw exception.