MVEL2.0模板（基本模板）

MVEL 2.0 Basic Templating

原文地址：http://mvel.codehaus.org/MVEL+2.0+Basic+Templating

MVEL Templates are compromised of orb-tags inside a plaintext document. Orb-tags denote dynamic elements of the template which the engine will evaluate at runtime.

If you are familiar with FreeMarker, this type of syntax will not be completely alien to you.

For a list of all orb-tags included in MVEL 2.0 click here

A Simple Template

Hello, @{person.getSex() == 'F' ? 'Ms.' : 'Mr.'} @{person.name}

This e-mail is to thank you for your interest in MVEL Templates 2.0.

This template shows a simple template with a simple embedded expression. When evaluated the output might look something like this:

Hello, Ms. Sarah Peterson

This e-mail is to thank you for your interest in MVEL Templates 2.0.

Escaping the @ symbol

Naturally, since the @ symbol is used to denote the beginning of an orb-tag, you may need to escape it, to prevent it from being processed by the compiler. Thankfully, there is only one situation where this is necessary: when you actually need to produce the string '@{' as output in your template.

Since the compiler requires a combination of @ and { to trigger the orb recognition, you can freely use @ symbols without escaping them. For example:

Email any questions to: [e-mail]

@{date}
@include{'disclaimer.html'}

But in the case where you need an @ symbol up-against an orb-tag, you will need to escape it by repeating it twice:

@{username}@@@{domain}

That's two @'s to escape one symbol, and the third @ being the beginning of the tag. If this looks too messy, you can always use the alternate approach of using an expression tag, like this:

@{username}@{'@'}@{domain}