While not mandatory, using the @Override annotation on compliant methods improves readability by making it explicit that methods are
overridden.
A compliant method either overrides a parent method or implements an interface or abstract method.
Noncompliant code example
class ParentClass {
  public boolean doSomething(){/*...*/}
}
class FirstChildClass extends ParentClass {
  public boolean doSomething(){/*...*/}  // Noncompliant
}
Compliant solution
class ParentClass {
  public boolean doSomething(){/*...*/}
}
class FirstChildClass extends ParentClass {
  @Override
  public boolean doSomething(){/*...*/}  // Compliant
}
Exceptions
This rule does not raise issues when overriding methods from Object (eg: equals(), hashCode(),
toString(), …).