Why does the conditional (ternary) operator (? :) in Java perform type casting?

I’ve been experimenting with the ternary operator (? :) in Java and noticed that it automatically performs type casting on its expressions. For example, this code returns 2.0 instead of 2:

System.out.println(false ? 1.0 : 2);

In a regular if-else conditional, Java obviously doesn’t perform type casting in the same way, but with the ternary operator, it does.

To determine the resulting type, I used the getClass() method for cases like differentiating between int and byte. For float or double versus int, the difference is obvious, as values like 2 become 2.0.

This raises a couple of questions:

1. Why does the Java ternary operator perform type conversion in the first place?

2. The operator seems to follow a typical Java type promotion hierarchy (e.g., byte -> short -> int -> long -> float). However, when int is involved, it always returns the other type if the int fits within the range of that type. For example, in the code below, the result is a byte with the value of 1:

System.out.println(true ? (int) 1 : (byte) 2);

This also applies to short in similar scenarios.

I haven’t tested all possible type combinations with the ternary operator, but sometimes the type casting behavior seems inconsistent or arbitrary.

How does Java decide which type to return in these cases?

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