Package hudson.plugins.emailext.groovy.sandbox

Class SimpleTemplateEngine

java.lang.Object

groovy.text.TemplateEngine

hudson.plugins.emailext.groovy.sandbox.SimpleTemplateEngine

public class SimpleTemplateEngine
extends groovy.text.TemplateEngine

Processes template source files substituting variables and expressions into placeholders in a template source text to produce the desired output.

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.SimpleTemplateEngine()
 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>SimpleTemplate</servlet-name>
   <servlet-class>groovy.servlet.TemplateServlet</servlet-class>
   <init-param>
     <param-name>template.engine</param-name>
     <param-value>groovy.text.SimpleTemplateEngine</param-value>
   </init-param>
 </servlet>
 

In this case, your template source file should be HTML with the appropriate embedded placeholders.

Author:

sam, Christian Stein, Paul King, Alex Tkachman

Field Summary

Fields

Modifier and Type	Field	Description
protected groovy.lang.GroovyShell	groovyShell
static int	MAX_EXPANDED_SIZE_BYTES	Maximum size of template expansion we expect to produce.

Constructor Summary

Constructors

Constructor	Description
SimpleTemplateEngine(groovy.lang.GroovyShell groovyShell, boolean sandbox)

Method Summary

Modifier and Type	Method	Description
groovy.text.Template	createTemplate(Reader reader)
groovy.text.Template	createTemplate(Reader reader, String fileName)
protected String	parse(Reader reader)	Parse the text document looking for <% or <%= and then call out to the appropriate handler, otherwise copy the text directly into the script while escaping quotes.
protected groovy.lang.Script	parseScript(Reader reader, String fileName)
protected String	printMethod()

Methods inherited from class groovy.text.TemplateEngine

createTemplate, createTemplate, createTemplate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MAX_EXPANDED_SIZE_BYTES

public static int MAX_EXPANDED_SIZE_BYTES

Maximum size of template expansion we expect to produce. Unit: bytes Default: 1MB

groovyShell

protected final groovy.lang.GroovyShell groovyShell

Constructor Detail

SimpleTemplateEngine

public SimpleTemplateEngine(groovy.lang.GroovyShell groovyShell,
                            boolean sandbox)

Method Detail

createTemplate

public groovy.text.Template createTemplate(Reader reader)
                                    throws org.codehaus.groovy.control.CompilationFailedException,
                                           IOException

Specified by:

createTemplate in class groovy.text.TemplateEngine

Throws:

org.codehaus.groovy.control.CompilationFailedException

IOException

createTemplate

public groovy.text.Template createTemplate(Reader reader,
                                           String fileName)
                                    throws org.codehaus.groovy.control.CompilationFailedException,
                                           IOException

Throws:

org.codehaus.groovy.control.CompilationFailedException

IOException

parseScript

protected groovy.lang.Script parseScript(Reader reader,
                                         String fileName)
                                  throws org.codehaus.groovy.control.CompilationFailedException,
                                         IOException

Throws:

org.codehaus.groovy.control.CompilationFailedException

IOException

parse

protected String parse(Reader reader)
                throws IOException

Parse the text document looking for <% or <%= and then call out to the appropriate handler, otherwise copy the text directly into the script while escaping quotes.

Parameters:

reader - a reader for the template text

Returns:

the parsed text

Throws:

IOException - if something goes wrong

printMethod

protected String printMethod()