Avoiding Common Mistakes

Following are the common beginner mistakes to avoid when declaring or using a boolean variables in apex.

Assuming default values

It is a common misconception that boolean variables are automatically initialized to false. However, this is not the case — in Apex, all data types are initialized to null when declared.

Assigning incorrect values

Boolean values can only accept true or false, and the following assignments result in compilation errors.

Comparison & Assignments

When comparing two boolean variables, always use the == operator instead of =. The = operator is only used for assignments (i.e., assigning a value to a variable). Using the = operator in a conditional statement will result in a compilation error.

Redundant comparison

Conditional statements always expect an expression to evaluates to true or false. But beginners commonly use the == comparison operators to compare with true or false, which is redundant. Using the boolean variable alone is sufficient for a conditional statement.

Negating booleans

When comparing a boolean variable to a negative value, always use the negation operator (!) rather than comparing it to false.