Java8

21.What is the purpose of IntSupplier functional interface? It represents a supplier of int-valued results.

11.What is the purpose of DoublePredicate functional interface? It represents a predicate (Boolean-valued function) of one double-valued argument.

1.What are functional interfaces? Functional interfaces have a single functionality to exhibit. For example, a Comparable interface with a single method ‘compareTo’ is used for comparison purpose. Java 8 has …