Author: Sergey Kargopolov

I’m a software developer with a passion for teaching. I’ve written lots of articles for AppsDeveloperBlog.com and made plenty of video tutorials on my YouTube channel(https://youtube.com/@SergeyKargopolov). If you want to dive deeper, I’ve also got some courses on Udemy(https://www.udemy.com/user/sergeykargopolov/) you might like.

When I’m not coding, I love to travel. I also share my travel adventures over at TravelLocalCanada.com. Hope to see you around on one of these platforms!

Web: www.appsdeveloperblog.com

In this tutorial, you will learn how to use change the background color of the top App Bar in Flutter. To change the background color of the AppBar widget in Flutter, we use its backgroundColor property. AppBar( backgroundColor: Colors.red ), // AppBar Below is a very simple Flutter app example, that uses the above code snippet…

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This tutorial will teach you how to start your Spring Boot Web application on a different port number. Read the following tutorial to learn how to start your Spring Boot application on a random port number. By default, if no port number is configured, our Spring Boot Web application will start on port number 8080.…

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This tutorial will teach you how to configure your Spring Boot application to log messages to a file. Specify File Path To make your application log messages to a file, you will need to configure a couple of new properties in the application.properties file. logging.file.path=/path/to/a/file logging.file.name=log.txt You might also need to enable a specific logging level…

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In this short tutorial, I am going to share with you how to switch your Spring Boot application, at runtime, to use a different logging level. Set Logging Level for a Package in Your App Suppose we have a Spring Boot Application with the following method in a Rest Controller class. @RestController @RequestMapping(“/users”) public class…

Read More Switch Logging Level in Spring Boot at Runtime

In this short tutorial, you will learn how to configure the /logout functionality in your Spring Boot Web application that uses OAuth2 Social Login. To learn how to implement the OAuth2 Social login feature, please check the following tutorial: Spring Security OAuth 2 Social Login. Configure HttpSecurity Applications that use Spring Security and OAuth2 Social login…

Read More Spring Security OAuth 2 Social Logout

In this tutorial, you will learn how to add a Social Login(OAuth 2) feature into your Spring MVC Web application. This will allow users to login to your application with their social network accounts like Facebook, Google, or other large services that support OAuth 2 like for example GitHub. Spring Security 5 offers very good…

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In this tutorial, you will learn about the main difference between the “mvn package” and “mvn install” commands. As well as how to use both commands on your computer. “mvn package” vs “mvn install” The main difference between the “mvn package” and “mvn install” commands is that mvn package command will compile the source and will package it in its…

Read More Difference Between “mvn package” and “mvn install”

Swift provides powerful tools for comparing and equating custom objects using the Comparable and Equatable protocols. In this tutorial, we will explore how to use the Comparable protocol to compare custom objects based on their properties, and the Equatable protocol to determine whether two objects are equal. By the end of this tutorial, you will…

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In this tutorial, you will learn how to get the currently authenticated principal user UserId value from the JWT access token generated by Keycloak. UserId in JWT The userId value will be stored under the “sub” key in the JWT access token generated by Keycloak. Below is an example of a decoded JWT access token containing…

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In this tutorial, you will learn how to use @AuthenticationPrincipal annotation to get the Jwt object containing the details of a provided in HTTP Request access token. When we send a request containing an access token in the Authorization header, behind the scenes,  Spring Framework will do a lot of work and if all is good,…

Read More @AuthenticationPrincipal – Getting the Jwt Claims

In this tutorial, you will learn how to refresh OAuth 2.0 access token using the Refresh Token OAuth 2.0 Grant Type. To learn how to use other OAuth 2.0 grant types, please check out the following tutorials: Client Credentials Grant Type with Keycloak, OAuth 2.0 Device Authorization Grant example, PKCE Verification in Authorization Code Grant,…

Read More OAuth 2.0 Refresh Token Example