- The document discusses various Java template engines that can be used on the JVM including Thymeleaf, Mustache, Jade, and Scalate. - A benchmark project was created to test the performance of these template engines in a Spring MVC application that renders a list of presentations. - The results showed that Thymeleaf used more memory and was slower than commonly used engines like Freemarker and Velocity. Mustache performed very well. Scalate was over 100 seconds slower due to its layout mechanism.

1. Shootout! Template
engines on the JVM
Jeroen Reijn | @jreijn | #jfall13

2. About me
• Architect @ Hippo
• Worked on web based platforms since
2001 with PHP, XSLT, JSP,Velocity and
Freemarker
• Blogger at http://blog.jeroenreijn.com

3. Session agenda
• General overview
• Interesting template engines
• Benchmark project
• Performance results

4. Template engine?
• What is a Template ?
• What is a Template Engine ?
• How many Java Template Engines ?
• Java-Source.net : 21
• Wikipedia: 17

5. Most commonly used
• JSP
• Freemarker
• Velocity

6. Overview

7. Selection criteria
• Project activity
• Framework support
• Active Community
• Brings added value
• IDE support

8. Most interesting
• Thymeleaf
• Mustache
• Jade
• Scalate

9. Thymeleaf

10. Overview
• Available at http://www.thymeleaf.org/
• Java, DOM based template engine
• XML / XHTML / HTML5
• Full Spring MVC integration
• ‘Natural templating’

11. Natural templating
• From Wikipedia:
“The template can be a document as valid as
the final result, the engine syntax doesn't
break the document's structure”

12. JSP in browser

13. Thymeleaf in browser

15. Variables & Loops
• Variables
• Loops

16. Fragments
• Include fragment
• Define fragment based on th:fragment

17. {{ Mustache }}

18. Overview
• Available at https://mustache.github.com
• “logic-less” because there are no control
statements (i.e. if, else, loops, etc)
• Tags are specified using {{ }} (looks like a
mustache)
• Implemented by many languages: Java, Ruby,
JavaScript, Python, Erlang, PHP, ObjectiveC, .NET, C++, Go, ColdFusion, Scala, etc.

19. Overview
• Java implementaions:
• JMustache
• Mustache.java
• Not web specific
• Spring MVC integration as an add-on

20. Variables
Data
{
}
“greeting” : “Hello”,
“message” : “World”
Template
{{greeting}} {{message}}
Output
Hello World

21. Sections
Data
{
"repo": [
{ "name": "resque" },
{ "name": "hub" },
{ "name": "rip" },
]
}
Template
{{#repo}}
<li>{{name}}</li>
{{/repo}}
Output
<li>resque</li>
<li>hub</li>
<li>rip</li>

22. Fragments
Template
base.mustache:
<h2>Presentations</h2>
{{#presentations}}
{{> presentation}}
{{/presentations}}
presentation.mustache:
<h3>{{title}}</h3>
<p>{{startTime}}</p>

23. Jade

24. Jade
• Available at http://jade-lang.com
• Node.js Template engine
• Java Implementation: Jade4j
• Compact notation

25. Syntax

26. Result

27. Variables & Iterations
• Variables
• Iterations

28. Fragments

30. Overview
• Available at http://scalate.fusesource.org/
• Scala based Template Engine (ScalaTE)
• Templates are compiled as Scala objects
• Equivalent to using JSP, JSTL, JSP EL & Tiles /
Sitemesh
• Integration available for Spring, Play, Lift, ...

31. Template languages
• SSP (Scala Server Pages)
• SCAML (based on Ruby’s HAML)
• Mustache
• Jade

32. Scaml
• Based on HAML (HTML abstraction
markup language)
• Integrates Scala code
• Well formatted markup
• Similar to Jade

33. Variables & Loops
• Fragment support is possible
• Inline Scala code

34. Benchmark project

35. Benchmark project
• Simple Spring MVC application
• Multiple view resolvers
• Page that show a list of presentations
• Uses page layouts / fragments
• Uses i18n where possible

36. Spring MVC

37. public class Presentation {
private Long id;
private String title;
private String speakerName;
private String summary;
private String room;
private Date startTime;
private Date endTime;
}

39. Project available
• Project will be available as open source on
github.
• https://github.com/jreijn/spring-comparingtemplate-engines

40. Results!

41. Performance
30,00s
Thymeleaf - v2.1.0
Jade4j - v0.3.17
Scalate - v1.6.1
Mustache - v1.8
Freemarker - v2.3.19
Velocity - v1.7
JSP - 2.1
26,50s
23,00s
19,50s
16,00s
12,50s
Total time taken for 25.000 requests (less is better)

42. Findings
• Thymeleaf used more memory and was
slower then the commonly used
• Scalate was a lot slower due to the layout
mechanism more than 100 seconds for
25.000 requests.
• Mustache performs really well

43. Tips
•
If you want designers to own your templates
consider Mustache or Thymeleaf
•
If you want developers to own your templates:
•
If you want to generate HTML / XML and DRY?
=> Jade
•
otherwise: JSP, Freemarker, etc

44. Thank you!
Questions?
@jreijn
j.reijn@onehippo.com