This tutorial will teach you how to add Spring Security to your project and enable in-memory basic authentication. You will learn how to configure two different users with different Roles and Privileges. Both users’ roles and privileges will be stored in the memory of your Spring Boot application. If you use Spring Framework and OAuth,…
Read More Spring Security In-Memory AuthenticationIn the world of testing, mock objects are used to simulate the behavior of real objects in the application. Mockito is a popular framework for creating mock objects in Java. A Spy in Mockito is a type of mock object that allows you to create a partial mock of an object by spying on an…
Read More Mockito Spy Explained: A Comprehensive GuideMockito enables partial mocking of an object, allowing us to create a mock object while still invoking a real method. To achieve this, we can use Mockito’s thenCallRealMethod() method to call a real method on a mocked object. I have also created several step-by-step video lessons that demonstrate how to test Java applications. If you…
Read More Mockito – Call a Real MethodI often find myself needing to run a single unit test for a particular project from the command line in my terminal window, rather than all of the tests. In this blog post, I’ll show you how to do just that: run a specific unit test using Maven from the command line. For video tutorials…
Read More Running a Single Unit Test with MavenIn this tutorial, you will learn how to write a JUnit test that validates whether the method under test throws the correct exception. The tutorial includes examples for both JUnit 5 and JUnit 4. For video lessons, check out my video course: Testing Java with JUnit and Mockito. Let’s begin with JUnit 5 version first.…
Read More Test for Exception in JUnit 5 and JUnit 4In this tutorial, I am going to share with you a few different techniques you can use to iterate over a collection in Java. Iterating ArrayList with Enhanced For-Loop List<String> names = new ArrayList<>(); names.add(“Sergey”); names.add(“Bill”); names.add(“John”); for(String name: names) { System.out.println(name); } Output: Sergey Bill John We declare a List of String objects named…
Read More Iterating over Collections in Java: ExamplesDependency injection is a design pattern in which a component’s dependencies are supplied externally rather than being hardcoded within the component itself. In Spring, developers mainly use 3 different types of dependency injection: constructor-based, setter-based, and field-based. In this tutorial, we will see how to use Setter-based Dependency Injection to inject a UsersRepository into a…
Read More Setter-based Dependency Injection in SpringLearning how to convert Java objects into JSON and vice versa can be very helpful for your work as a full-stack mobile app developer. In this blog post, I will share some code examples that will help you with the most common tasks you’ll encounter when working with JSON and Java. I will cover the…
Read More Convert Java into JSON and JSON into Java. All Possible Examples.Maven is a popular build tool for Java projects. It helps you manage dependencies, build and test your projects, and package them for distribution. Keeping Maven up-to-date is important to take advantage of the latest bug fixes and new features. If you do not have Maven installed on your computer, then read How to install…
Read More Upgrading Maven on macOSSpring is a popular Java-based framework for building applications. One of its core features is dependency injection, which is used to manage the relationships between objects and to make it easier to manage the dependencies in an application. In this tutorial, we will explore two of the main methods of dependency injection in Spring: constructor…
Read More Constructor vs Field Dependency Injection in SpringThis tutorial will teach you how to start your Spring Boot application on a random port number. Starting an application on a random port number is very helpful when you need to start multiple instances of the same Spring Boot application and then balance HTTP requests between the running instances. If you want to learn…
Read More Start Spring Boot App on a Random Port NumberDependency Injection is a design pattern that allows the separation of concerns in an application by removing the hard-coded dependencies between objects. In Dependency Injection, the objects are provided with their dependencies instead of having to hard-code them. This makes the application more flexible, maintainable, and easier to test. Spring Framework provides several ways to…
Read More Field-based Dependency Injection in SpringInstalling an SSL certificate on a Bitnami stack for Lightsail is a simple process that can be completed in just a few steps. In this blog post, we will walk you through the process of installing an SSL certificate on your Bitnami stack for Lightsail. You can use the generated SSL certificate for your LAMP…
Read More Install SSL certificate on Bitnami stack for LightsailAWS Lambda is a service that lets you run code without provisioning or managing servers. In this tutorial, I will share with you how to create a very simple Lambda function in Java and run it on AWS. Prerequisites To be able to follow this tutorial, you will need to have the following: An AWS account,…
Read More A Simple AWS Lambda Function in JavaIn this tutorial, you will learn how to download and start up Keycloak as a standalone server. What is Keycloak? Keycloak is an open-source identity and access management tool focusing on modern applications and services such as mobile applications, REST APIs, and single-page applications. How to Download Keycloak? To download the Keycloak go to the…
Read More Keycloak: Starting a Standalone Server