java functional interface example

Example 1: interface function

interface SearchFunc {
  (source: string, subString: string): boolean;
}

Example 2: creating the functional interface in java

package com.concretepage;

@FunctionalInterface
public interface Calculator {
   long calculate(long num1, long num2);
}

Example 3: functional interface java

A functional interface is an interface that contains only one abstract method. They can have only one functionality to exhibit.