org.webbitserver.handler
Interface TemplateEngine

All Known Implementing Classes:

StaticFile

public interface TemplateEngine

Abstract interface for template engines. It can be passed as an argument to the constructors of StaticFileHandler and EmbeddedResourceHandler.

Webbit itself doesn't provide any template engines. Look at Webbit-REST for implementations.

Field Summary

static String

TEMPLATE_CONTEXT

Method Summary

byte[]

process(byte[] template, String templatePath, Object templateContext) Renders a template.

Field Detail

TEMPLATE_CONTEXT

static final String TEMPLATE_CONTEXT

See Also:

Constant Field Values

Method Detail

process

byte[] process(byte[] template,
               String templatePath,
               Object templateContext)
               throws RuntimeException

Renders a template.

Most template engines merge a templateContext with a template to produce output. What constitutes a valid context is template-engine specific.

Rendering happens on your main thread, so it is important that this method is not IO-bound. For example, rendering a template using a context that is some sort of active record that makes trips to the database will block Webbit preventing it from handling other requests. It's important to make sure any remote data is pre-fetched.

Webbit will pass the request data value keyed with TEMPLATE_CONTEXT as the templateContext argument. It's the programmer's responsibility to make sure the data value is set before the template is rendered, i.e. before the StaticFileHandler or EmbeddedResourceHandler handler instance handles a request.

Parameters:

length - number of bytes in the template

template - the template source

templatePath - the path the template is read from. Allows implementations to cache compiled templates.

templateContext - object to merge into the template

Returns:

a rendered template

Throws:

RuntimeException

See Also:

DataHolder.data(String), HttpRequest.data(String, Object)