functional-interface

I am trying to convert to Lambda function So far I am able to convert the above code to lambda function like as shown below Stream.of(acceptedDetails, rejectedDetails) .filter(list -> !isNull(list) && list.length > 0) .forEach(new Consumer<Object>() { public void accept(Object acceptedOrRejected) { String id; if(acceptedOrRejected instanceof EmployeeValidationAccepted) { id = ((EmployeeValidationAccepted) acceptedOrRejected).getId(); } else { id = ((EmployeeValidationRejected) acceptedOrRejected).getAd().getId(); } if(acceptedOrRejected instanceof EmployeeValidationAccepted) { dates1.add(new

wrote java8 program with lambda expression, its not getting executed instead its getting terminated at the lambda expression, no exceptions import java.util.ArrayList; import java.util.List; import java.util.function.BiConsumer; public class BiConsumerTest { public static void main(String[] args) { try{ List<String> list1 = new ArrayList<String>(); list1.add("A"); list1.add("B"); list1.add("V"); List<String> list2 = new ArrayList<String>(); list2.add("J"); list2.add("G"); list2.add("P"); BiConsumer<List<String> , List<String>> bc = (lista, listb) ->{ lista.stream().forEach( System.out::print);

This question already has an answer here: Precise definition of “functional interface” in Java 8 6 answers The definition of a functional Interface in Java 8 says: A functional interface is defined as any interface that has exactly one explicitly declared abstract method. (The qualification is necessary because an interface may have non-abstract default methods.) This is why functional interfaces used to be called Single Abstract Method (SAM) interfaces, a term that is still sometimes seen. So how come we have this: List<Double> temperature = new ArrayList<Double>(Arrays.asList(new Double[] {

I was learning to write some lambda representation as FunctionalInterface . So, to add two integers I used: BiFunction<Integer, Integer, Integer> biFunction = (a, b) -> a + b; System.out.println(biFunction.apply(10, 60)); Gives me the output 70 . But if I write it as this BinaryOperator<Integer, Integer, Integer> binaryOperator = (a, b) -> a + b; I get an error saying Wrong number of type arguments: 3; required: 1 Isn't BinaryOperator a child of BinaryFunction ? How do I improve it? BinaryOperator Since BinaryOperator works on a single type of operands and result . i.e. BinaryOperator<T> . Isn

This question already has answers here : Is there a way to compare lambdas? (3 answers) Closed 4 years ago . I am not sure how I can be sure about equality/immutability of functional interface. I guess there might be no way to assure equality when I use this syntactic sugar in java 8, please let me know any hint if you have any. I made a short code snippet for my question. public interface Element { void doSomething(int a); } and I've tried to add instance of this interface in functional way public class FunctionSet { public void doubleUp(int a) { System.out.println(a*2); } public void square

I have a String as "ishant" and a Set<String> as ["Ishant", "Gaurav", "sdnj"] . I need to write the Predicate for this. I have tried as below code, but it is not working Predicate<Set<String>,String> checkIfCurrencyPresent = (currencyList,currency) -> currencyList.contains(currency); How can I create a Predicate which will take Set<String> and String as a parameter and can give the result? A Predicate<T> which you're currently using represents a predicate (boolean-valued function) of one argument . You're looking for a BiPredicate<T,U> which essentially represents a predicate (boolean-valued