Last updated: 2024-05-07
Angular vs Thymeleaf - comparison and selection
Angular and Thymeleaf can both be used for the frontend of browser applications with Spring Boot. The following article provides an overview of the two technologies and a rough guideline as to which language should be chosen.
Thymeleaf in a nutshell
Thymeleaf is Spring Boots most popular template engine and used for server-side rendering. In practice, this means that the model is first prepared in a Spring MVC controller and provided to the selected template.
A simple Spring MVC controller
In the following template, the texts are read from messages.properties using [[#{...}]]. The control logic takes place via the th:if and th:each tags.
A simple Thymeleaf template
Although the templates still have to be interpreted, each file can be opened in the browser on its own. Since Thymeleaf itself does not provide any browser logic, either an app.js or a complex Node.js setup is integrated into the Spring Boot app. HTMX can also be a nice extension to integrate typical JavaScript logic as simple HTML attributes into the application.
Angular short and sweet
Angular provides a dedicated, complex framework for the frontend. The HTML structure and logic are provided with the Angular code. A typical component could look like this.
An Angular standalone component
The HTML code including the logic is provided in another file book-list.component.html. Angular comes with a template syntax for the logical control.
An Angular template
Since the messages.properties is not available, we use Angular's native approach for localization. Communication to the Spring Boot backend takes place exclusively via a REST API or GraphQL.
Selection of technology
Thymeleaf has been available for a very long time and therefore also provides a ton of helpers. Some parts of the syntax seem clunky at first, but with a little practice the templates are basically self-explanatory. A large part of the logic happens in the backend, so that all the powerful features of Java and Spring Boot can be used.
Angular enjoys great popularity for good reason and is particularly suitable for complex, client-heavy applications, that is, when a lot of control is required directly in the browser. Due to the regular updates, Angular also involves higher migration costs - for example, the new template syntax was only introduced with Angular 17. Spring MVC with Thymeleaf seems to be the better choice for relatively simple applications that should be operated with little effort in the long term.
In the Bootify Builder, a Spring Boot prototype with a Thymeleaf or Angular frontend can be created. This allows to compare them and to select the most suitable technology for your next project.
