Java 8

The main changes of the Java 8 release were these:

· Lambda Expression and Stream API

· Method Reference

· Default Methods

· Type Annotations

· Repeating Annotations

· Method Parameter Reflection

Java 9

Java 9 introduced these main features:

· Java Module System

· Try-with-resources

· Diamond Syntax with Inner Anonymous Classes

· Private Interface Methods

Java 10

Local Variable Type Inference

Implicit Typing with var

Java 11

Local Variable Type in Lambda Expressions

Java 14

Switch Expressions

Switch expressions allowed us to omit break calls inside every case block. 

Using Switch Expressions

days = switch (month) {

            case JANUARY, MARCH, MAY, JULY, AUGUST, OCTOBER, DECEMBER -> 31;

            case FEBRUARY -> 28;

            case APRIL, JUNE, SEPTEMBER, NOVEMBER -> 30;

            default -> throw new IllegalStateException();

        };

The yield Keyword

days = switch (month) {

            case JANUARY, MARCH, MAY, JULY, AUGUST, OCTOBER, DECEMBER -> {

                System.out.println(month);

                yield 31;

            }

Java 15

Text Blocks “””

Java 16

Pattern Matching of instanceof

defining variable Car c and Bicycle b

public class PatternMatching {

    public static double price(Vehicle v) {

        if (v instanceof Car c) {

            return 10000 - c.kilomenters * 0.01 -

                    (Calendar.getInstance().get(Calendar.YEAR) -

                            c.year) * 100;

        } else if (v instanceof Bicycle b) {

            return 1000 + b.wheelSize * 10;

        } else throw new IllegalArgumentException();

    }

}

Records

public record VehicleRecord(String code, String engineType) {}

we cannot extend a record class

Java 17

Sealed Classes

public sealed class Vehicle permits Bicycle, Car {...}

The final modifier on a class doesn’t allow anyone to extend it

What about when we want to extend a class but only allow it for some classes?

public sealed class Vehicle permits Bicycle, Car {...}