Which methods are being used as an abstract method for functional interface?

Looking under the java built in interface,

Comparator<T>

Comparator<T>

functional interface has 2 non default methods,

int compare(T o1, T o2)

int compare(T o1, T o2)

and

boolean equals(Object obj)

boolean equals(Object obj)

. My question is asking the reason of why the latter method does not need to be implemented when using lambda/anonymous, what determines which method is being used as the functional method within the interface.

As of what I understand, functional interface may only take one abstract method to be implemented, but how does it know which method is needed to be implemented during an anonymous class/lambda calls?

My logic is that Comparator takes generic

, so that it find the following abstract method that uses

as the parameters, such as

int compare(T o1, T o2)

int compare(T o1, T o2)

. OR in another case, because of the order of method declaration.

Which methods are being used as an abstract method for functional interface?

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