How to Calculate Holidays in Java

I have experience working in a system that utilizes a technology where we cannot employ any library to calculate holidays. I can tell you that implementing this type of logic is highly sensitive, and depending on the system, it can have a significant impact. This is because certain transactions can only take place on business days, and if your system incorrectly calculates a holiday, you may incur financial losses.

Fortunately, in Java, we don’t need to worry about implementing such logic from scratch. We can utilize existing libraries for this purpose, one of which I have worked with is the Holiday Calculator (https://github.com/itsallcode/holiday-calculator).

Let’s explore this nice library.

Installation

Add the following dependency to your pom.xml file.

<dependency>
    <groupId>org.itsallcode</groupId>
    <artifactId>holiday-calculator</artifactId>
    <version>0.2.0</version>
</dependency>

Configuration

After installing this library in your project, you need to configure the holidays. One way to do this is by creating Holiday objects, each representing a holiday definition within the Holiday class. The Holiday class is abstract and has six implementations to allow the creation of holidays: