Boolean expressions should not be compared against boolean literals, as their value can be directly used.
The following code:
if (booleanVariable == true) { /* ... */ } // Non-Compliant if (booleanVariable != true) { /* ... */ } // Non-Compliant
should be refactored into:
if (booleanVariable) { /* ... */ } // Compliant if (!booleanVariable) { /* ... */ } // Compliant