Can an int be null in Java?
java
Solution
`int` can't be null, but `Integer` can. You need to be careful when unboxing null Integers since this can cause a lot of confusion and head scratching!
e.g. this:
int a = object.getA(); // getA returns a null Integer
will give you a `NullPointerException`, despite object not being null!
To follow up on your question, if you want to indicate the absence of a value, I would investigate `java.util.Optional<Integer>` or `java.util.OptionalInt`
Problem
Can an `int` be `null` in Java? For example: ``` int data = check(Node root); if ( data == null ) { // do something } else { // do something } ``` My goal is to write a function which returns an `int`. Said `int` is stored in the height of a node, and if the node is not present, it will be null, and I'll need to check that. I am doing this for homework but this specific part is not part of the homework, it just helps me get through what I am doing. Thanks for the comments, but it seems very few people have actually read what's under the code, I was asking how else I can accomplish this goal; it was easy to figure out that it doesn't work.