Expressions should not be too complex

The complexity of an expression is defined by the number of &&, || and condition ? ifTrue : ifFalse operators it contains. A single expression's complexity should not become too high to keep the code readable.

The following code, with a maximum complexity of 3:

if (condition1 && condition2 && condition3 && condition4) { /* ... */ }  // Non-Compliant

could be refactored into something like:

if (relevantMethodName1() && relevantMethodName2()) { /* ... */ }        // Compliant

/* ... */

private boolean relevantMethodName1() {
  return condition1 && condition2;
}

private boolean relevantMethodName2() {
  return condition3 && condition4;
}