public class GStringTemplateEngine extends TemplateEngine
SimpleTemplateEngine
but creates the template using writable
closures making it potentially more scalable for large templates or in streaming scenarios.
The template engine uses JSP style <% %> script and <%= %> expression syntax
or GString style expressions. The variable 'out
' is bound to the writer that the template
is being written to.
Frequently, the template source will be in a file but here is a simple example providing the template as a string:
def binding = [ firstname : "Grace", lastname : "Hopper", accepted : true, title : 'Groovy for COBOL programmers' ] def engine = new groovy.text.GStringTemplateEngine() def text = '''\ Dear <%= firstname %> $lastname, We <% if (accepted) print 'are pleased' else print 'regret' %> \ to inform you that your paper entitled '$title' was ${ accepted ? 'accepted' : 'rejected' }. The conference committee. ''' def template = engine.createTemplate(text).make(binding) println template.toString()This example uses a mix of the JSP style and GString style placeholders but you can typically use just one style if you wish. Running this example will produce this output:
Dear Grace Hopper, We are pleased to inform you that your paper entitled 'Groovy for COBOL programmers' was accepted. The conference committee.The template engine can also be used as the engine for
TemplateServlet
by placing the
following in your web.xml
file (plus a corresponding servlet-mapping element):
<servlet> <servlet-name>GStringTemplate</servlet-name> <servlet-class>groovy.servlet.TemplateServlet</servlet-class> <init-param> <param-name>template.engine</param-name> <param-value>groovy.text.GStringTemplateEngine</param-value> </init-param> </servlet>In this case, your template source file should be HTML with the appropriate embedded placeholders.
Constructor and Description |
---|
GStringTemplateEngine() |
GStringTemplateEngine(ClassLoader parentLoader) |
Modifier and Type | Method and Description |
---|---|
Template |
createTemplate(Reader reader) |
createTemplate, createTemplate, createTemplate
public GStringTemplateEngine()
public GStringTemplateEngine(ClassLoader parentLoader)
public Template createTemplate(Reader reader) throws CompilationFailedException, ClassNotFoundException, IOException
createTemplate
in class TemplateEngine
CompilationFailedException
ClassNotFoundException
IOException