Java Booleans

Why are booleans not considered an object? 
Simply put, primitive types like boolean, int, float, and double are not objects because they are not a subclass of Object. Additionally, they do not have methods. Here are two good answers for this question: 
 (Links to an external site.) 

When are primitive booleans best used? 
Booleans are most often used within if statements and while loops. Booleans are used whenever a truth value should be stored to be later referenced. For instance, if a truth value would otherwise be computed multiple times, it might be easier and more efficient to store the truth value in a boolean variable.

How can boolean values be combined?
Since a boolean is just a truth value, the combination of boolean variables and operations are treated as a combination of truth values. 
Simple combinations can be seen here: 
While more complex truth value operations can be seen here: