Interface is a very popular way to expose our APIs. Until Java 7 it was getting used as a contract (abstract method) where a child class was obliged to implement the contract; but after Java 8, Interface got more power — to where we can have static and default methods. In Java 9, Interface is getting more power, to the point where we can define private methods as well. Let us understand why we need private methods in Interfaces....
Interface was meant to define a contract before Java 8, where we were able to define the methods a class needed to implement if binding himself with the interface. Interface was only involved with abstract methods and constants. But in Java 8, Interface has become much more, and now it can have methods defined using static or default. Remember that default methods can be overridden, while static methods cannot. Method Definitions Interface was meant for good designers because when we create an Interface, we should know the possible contract that every class should implement....
Over the years spring has become more and more complex as new functionalities have been added. Just visit the page-https://spring.io/projects and we will see all the spring projects we can use in our application for different functionalities. If one has to start a new spring project we have to add build path or add maven dependencies, configure application server, add spring configuration . So a lot of effort is required to start a new spring project as we have to currently do everything from scratch....
SDKMAN! is a tool for managing parallel versions of multiple Software Development Kits on most Unix based systems. It provides a convenient Command Line Interface (CLI) and API for installing, switching, removing and listing Candidates. Formerly known as GVM the Groovy enVironment Manager, it was inspired by the very useful RVM and rbenv tools, used at large by the Ruby community. Install Software Development Kits for the JVM such as Java, Groovy, Scala, Kotlin and Ceylon....
Take the following interface: public interface Cooking { public void fry(); public void boil(); public void chop(); } To add new functionality, simply adding a new method to Cooking called microwave() will cause problems. Any class that previously implemented Cooking will now have to be updated in order to function again. To avoid this, give microwave() a default implementation: public interface Cooking { public void fry(); public void boil(); public void chop(); default void microwave() { //some code implementing microwave } } As microwave() already has a default implementation defined in the Cooking interface definition, classes that implement it now don’t need to implement microwave() in order to work....