In Java, what are the boolean "order of operations"?

Solution 1:

The Java Tutorials has a list illustrating operator precedence. The equality operators will be evaluated first, then &&, then ||. Parentheses will be evaluated before anything else, so adding them can change the order. This is usually pretty much the same from language to language, but it's always a good idea to double check.

It's the small variations in behavior that you're not expecting that can cause you to spend an entire day debugging, so it's a good idea to put the parentheses in place so you're sure what the order of evaluation will be.

Solution 2:

Boolean order of operations (in all languages I believe):

1. parens
2. NOT
3. AND
4. OR

So your logic above is equivalent to:

(cat != null && cat.getColor() == "orange") || cat.getColor() == "grey"