JSTL vs Thymeleaf: What are the differences?

Introduction

JSTL (JavaServer Pages Standard Tag Library) and Thymeleaf are both popular technologies used in Java web development. While they serve similar purposes, there are several key differences between the two.

1. Syntax: JSTL uses XML-like tags and expressions within JSP (JavaServer Pages) files, making it more similar to traditional HTML. Thymeleaf, on the other hand, uses a custom syntax with attributes and expressions embedded directly in HTML tags, resulting in more readable and natural HTML templates.

2. Ease of Learning: Thymeleaf is generally considered easier to learn and use compared to JSTL. Its HTML-like syntax and seamless integration with HTML tags make it more intuitive for developers, especially those with front-end experience. JSTL, with its XML-like syntax, may require additional effort and familiarity with JSP to fully grasp.

3. Server-Side vs Client-Side Rendering: JSTL operates on the server-side, where the JSP files are processed and transformed into HTML before being sent to the client's browser. Thymeleaf, on the other hand, supports both server-side and client-side rendering. This means that Thymeleaf templates can be processed on the server-side or shipped as-is to the client, where JavaScript can handle dynamic rendering.

4. Integration with Spring Framework: Thymeleaf has seamless integration with the Spring Framework, one of the most popular Java frameworks for web development. It provides several powerful features, such as automatic form binding and Spring Expression Language (SpEL) integration. Although JSTL is also commonly used with Spring, it requires some additional configuration and may not have the same level of integration and convenience as Thymeleaf.

5. Rich Templating Features: Thymeleaf offers a wide range of powerful templating features that enable developers to build complex HTML templates. These features include conditional rendering, iteration, internationalization support, and more. While JSTL also provides some templating capabilities, Thymeleaf's feature set is generally more extensive and flexible.

6. Client-Side DOM Manipulation: Thymeleaf, with its support for client-side rendering, allows developers to easily manipulate the Document Object Model (DOM) of a webpage using JavaScript, resulting in dynamic and interactive UIs. In contrast, JSTL operates entirely on the server-side and does not provide direct support for client-side DOM manipulation.

In summary, Thymeleaf offers a more intuitive syntax, easier learning curve, and seamless integration with the Spring Framework. It also provides richer templating features and supports both server-side and client-side rendering. JSTL, on the other hand, uses an XML-like syntax, operates solely on the server-side, and may require more effort to learn and configure.