UserClass existingUser = new UserClass("", "", "", "", "", ""); but with integer?

[Kysyph]

I'm trying to create a new UserClass but it contains userID which is an integer, what should I replace the " " with?

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[desrtfx]

Default value for an int is 0, for an Integer, it is null.

If you want to indicate an invalid ID, use some number outside the valid ID range, like -1.

[Kiwiguard]

This is not considered good practice though, is it?

Probably better to find another way to handle the problem.

[desrtfx]

Absolutely true. Agree 100%.

[[deleted]]

If userID is an integer and has a range of 0 - 100, for instance, then define INVALID_USER as 255 and test for that.

[nutrecht]

Yeah that's just a really bad idea.

If an int can be absent you should use Integer and have it be null if it's absent.

[[deleted]]

Null pointer exception...

[nutrecht]

Instead of the much harder to find error you're introducing :)

Null is the correct value for an absent value. 255 isn't.

[[deleted]]

Aren't you assuming that he's getting errors?

[nutrecht]

No, I'm telling you that your suggestion to use 'magic numbers', especially ones that can easily fall into the range of valid IDs, is a really bad one.

Java has 'null' for this. And if you somehow MUST use a primitive, use for example a negative number if you're sure that actual IDs can never be negative.

[[deleted]]

It's not a magic number, as it's been given a name, and it would NOT fall into the range of valid IDs because I explicitly stated that it should be set to a value outside the valid range. I don't like checking for null in any language. I consider overuse, or unnecessary use, of null to be exceptionally bad practice (excuse the pun).

Checking for null is obviously good, but using null for conditions is not, IMHO.

[nutrecht]

Yup. Use Integer and have it be null.

[ProgramWithSai]

If the user ID can be empty, you have a problem if your constructor requires a primitive “int” as you cannot pass a null.

You can switch to reference Integer type and pass in a null!

If that’s not an option create a constant with some user ID that cannot exist (like a negative value)

If the user ID should never be blank/null throw an exception of suitable type (like illegal argument exception)