Expressions of type boolean

The following are simple expressions of type boolean:

• The constants true, false;
• Variables declared of type boolean;
• Comparison operators applied to primitive data types: == , != , > , < , >= , <=
• Calls to predicates (i.e., methods that return a value of type boolean).

Complex expressions can be constructed from simple boolean expressions using the boolean operators !, &&, and ||. For such operators, the following precedences hold:

1. !
2. &&
3. ||

Example: The following is a correct expression of type boolean:

a || ! b && c

It is equivalent to:

a || ((! b) && c)