Roy Tutorials

React Spring Security Here in this example I am going to integrate React JS front-end with Spring Boot Security framework. When user will try to access the home page the user will be redirected to the login page if the user has not been authenticated already. Spring Boot’s default security mechanism asks for username and password when a user tries…

Microservices And Load Balancer Microservice, also known as, microservice architecture is an architectural style with an approach for developing a single application as a suite of small services, each running in its own process and communicating with a lightweight resource API that has the following characteristics:

Organization Chart Here I am going to build google organization chart using spring boot framework. Organization chart can be used to display hierarchical data of an organization, for example, you can display the employees and their managers in hierarchical order. You can also find the organization hierarchy in your organization also. For example, you can see your manager, your manager’s…

Asynchronous Data Here I am going to show you how to fetch data asynchronously. So, data which are not coordinated in time will be fetched any time. This means that data is sent at irregular intervals, without any specific time or synchronization between the sender and receiver. In this example I am going to use CompletableFuture from Java 8’s new…

Hikari Connection Pool Here in this Spring Boot application example, I am going to show you how to use Hikari connection pool to use dedicated HikariDataSource instead of the use of database specific datasource. Hikari connection pool commonly known as HikariCP is extremely fast, light-weight, simple and production ready JDBC connection pool.

Spring Batch I have already written some posts on Spring Batch. I am going to show you here what are the changes required while you are migrating your existing spring batch application to spring batch version 5.x or while you are using spring batch in spring boot 3.x. Requirements For Spring Batch 5 Implementation Related Changes Here are some changes…

Multiple DataSources In Spring Batch Here I am going to show you how to use multiple datasources in spring batch application. You may need to use multiple data sources for various reasons, for example, you may need to store table metadata for spring batch into h2 database and other business data into Oracle, MySQL or any other database. Or another…

REST API Multiple Files Upload In this tutorial I am going to show you an example how to upload multiple files using REST (Representational State Transfer) API. I will also create a client program to upload multiple files through REST API. I am not using any Postman or SOAP UI tool to test the file upload functionality, so I am…

REST API File Upload I am going to show you how to upload single file using REST API in PHP language. The full form of REST is Representational State Transfer. I will use POST method to upload the file. The REST API will get the file content from the client and will store the file content to a specified destination….

In this example I am going to show you how to test file upload using Spring Boot Rest Template API. You can always use any REST based testing tools, such as, Postman, Talend, etc. but when you do not have any access to such REST based client tools, for example, your organization has blocked access to such REST client tools….