Java

public class App { public static void main(String[] args) { // … } } public class App { public static void main(String[] args) { for(String s : args) { System.out.println(s); } } } public static void main(String[] args) public static void main(String []args)  public static void main(String args[]) public static void main(String… args) static public void main(String[] args) public static final void main(String[] args) final public static void main(String[] args)

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class Vehicle { int maxSpeed = 250; public void printMaxSpeed() { System.out.println(“Max speed: ” + maxSpeed); } } class Car extends Vehicle { int maxSpeed = 300; @Override public void printMaxSpeed() { System.out.println(“Max speed: ” + maxSpeed); } } class Test { public static void main(String[] args) { Vehicle vehicle = new Car(); // upcasting…

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public class Test { public static void main(String[] args) { String str = “Learn Java with alegrucoding.com”; String result = str.replaceAll(“\\s”, “”); System.out.println(result); } } Output: LearnJavawithalegrucoding.com import org.apache.commons.lang3.StringUtils; public class Test { public static void main(String[] args) { String str = “Learn Java with alegrucoding.com”; String result = StringUtils.deleteWhitespace(str); System.out.println(result); } } Output: LearnJavawithalegrucoding.com

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In this tutorial, you will learn how to write a JUnit Test that validates if the method under the test throws the correct exception. This tutorial will have examples for JUnit 5 and JUnit 4 as well. Let’s begin with JUnit 5 version first. JUnit 5. “assertThrows()” Assertion To test for exceptions in JUnit 5…

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In this article, we will cover the basics of Aspect-Oriented Programming (AOP). You will learn how to use AspectJ to provide different AOP advices to Spring Boot applications to support cross-cutting issues like logging, profiling, caching, and transaction management and finally we will do a practical implementation to record user operations using Spring Boot AOP.…

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In this tutorial, you will learn about JUnit5 Lifecycle methods. A Lifecycle Method is any method that is directly annotated or meta-annotated with @BeforeAll, @AfterAll, @BeforeEach, or @AfterEach. Let’s have a look at these annotations one by one. @BeforeAll When a method is annotated with @BeforeAll it means that the method should be executed before…

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