ToLongBiFunction is a in-built functional interface from java.util.function package. This functional interface accepts two reference type parameters as input and produces a long-valued result. ToLongBiFunction interface can be used as an assignment target for a lambda expression or method reference and contains only one abstract method: applyAsLong().Syntax@FunctionalInterface interface ToLongBiFunction {  long applyAsLong(T t, U u); ... Read More

ToLongFunction is a functional interface defined in java.util.function package. This functional interface accepts a reference type as input and produces a long-valued result. ToLongFunction interface can be used as an assignment target for a lambda expression or method reference. It contains only one abstract method: applyAsLong().Syntax@FunctionalInterface interface ToLongFunction {    long applyAsLong(T value); }Exampleimport java.util.*; import java.util.function.ToLongFunction; ... Read More

ToIntBiFunction is a built-in functional interface from java.util.function package. This interface accepts two parameters as input and produces an int-valued result. ToIntBiFunction interface can be used as an assignment target for a lambda expression or method reference. It contains only one abstract method: applyAsInt() and doesn't contain any default or static methods.Syntax@FunctionalInterface interface ToIntBiFunction {    int applyAsInt(T t, U u); ... Read More

ToDoubleBiFunction is a functional interface defined in java.util.function package. This functional interface accepts two parameters as input and produces a double-valued result. ToDoubleBiFunction interface can be used as an assignment target for a lambda expression or method reference. This interface contains only one abstract method: applyAsDouble() and doesn't contain any default or static methods.Syntax@FunctionalInterface interface ToDoubleBiFunction { ... Read More

A Map interface implements the Collection interface that provides the functionality of the map data structure. A Map doesn't contain any duplicate keys and each key is associated with a single value. We can able to access and modify values using the keys associated with them.In the below two examples, we can able to sort a Map by both ... Read More

LongUnaryOperator is a functional interface from java.util.function package. This functional interface accepts a single long-valued operand and produces a long-valued result. LongUnaryOperator interface can be used as an assignment target for lambda expression and method reference. It contains one abstract method: applyAsLong(), one static method: identity() and two default methods: andThen() and compose().Syntax@FunctionalInterface public interface LongUnaryOperator  long ... Read More

The variables defined by the enclosing scope of a lambda expression can be accessible within the lambda expression. A lambda expression can access to both instance, static variables and methods defined by the enclosing class. It has also access to "this" variable (both implicitly and explicitly) that can be an instance of enclosing class. The ... Read More

Method reference is one of a way in a lambda expression to refer a method without executing it. In the body part of a lambda expression, we can call another method if they are compatible with a functional interface. We can also capture "this" and "super" keywords in method references.In the below two examples, ... Read More

DoubleUnaryOperator is a functional interface defined in java.util.function package. This functional interface expects a parameter of type double as input but produces the output of the same type. DoubleUnaryOperator interface can be used as an assignment target for lambda expression and method reference. This interface contains one abstract method: applyAsDouble(), one static method: identity() and two default methods: ... Read More

LongSupplier is a built-in functional interface from java.util.function package. This interface doesn’t expect any input but produces a long-valued output. Since LongSupplier is a functional interface, it can be used as an assignment target for lambda expression and method reference and contains only one abstract method: getAsLong().Syntax@FunctionalInterface public interface LongSupplier {  long getAsLong(); }Example of Lambda Expressionimport java.util.function.LongSupplier; ... Read More