How To Program Blog

This tutorial is going to cover how to install a Spring Boot application as a Linux service, which enables us to start, stop and check application status using standard commands such as: service start payment-service, service stop payment-service and service… Continue Reading →

1. Overview In this tutorial, we’re going to see to how set up environment variables for applications deployed in Apache Tomcat. 1. Set up Environment Variables For Apache Tomcat On Windows One popular approach to set up environment variables for… Continue Reading →

This tutorial is going to cover how to create a data frame in R. We’re going to get through how to: Create data frames from Vectors. Create data frames from existing data frames. Create data frame a List. 1. Create… Continue Reading →

This tutorial is going to cover how to lookup Java enum from string value. 1. Lookup Enum From Value With Simple Enum Type Let’s assume that we have a simple enum as follows: To lookup a Java enum from its… Continue Reading →

In this short tutorial, we’re going to explore how to use JUnit 5 and Mockito, a popular mocking framework for unit tests written in Java. 1. JUnit 5 and Mockito Dependencies 1.1. Maven Dependencies At first, let’s take a look… Continue Reading →

In this tutorial, we’re going to show how to remove or delete a column of a data frame in R. 1. Preparation Let’s create a data frame which will be used for all examples in this tutorial:

And let’s… Continue Reading →

This tutorial is going to illustrate how to sort or order a data frame in R. 1. Preparation Let’s assume that we have a small data frame about books as follows, which will be used for all examples in this… Continue Reading →