BAEL-2782 Template engines in groovy

core-groovy-2/src/main/resources/articleEmail.template

@@ -0,0 +1,5 @@
+Dear <% out << (user) %>,
+Please read the requested article below.
+<% out << (articleText) %>
+From,
+<% out << (signature) %>

core-groovy-2/src/main/resources/email.template

@@ -0,0 +1,3 @@
+Dear $user,
+Thanks for subscribing our services.
+${signature}

core-groovy-2/src/test/groovy/com/baeldung/templateengine/TemplateEnginesUnitTest.groovy

@@ -0,0 +1,96 @@
+package com.baeldung.templateengine
+
+import groovy.text.SimpleTemplateEngine
+import groovy.text.StreamingTemplateEngine
+import groovy.text.GStringTemplateEngine
+import groovy.text.XmlTemplateEngine
+import groovy.text.XmlTemplateEngine
+import groovy.text.markup.MarkupTemplateEngine
+import groovy.text.markup.TemplateConfiguration
+
+class TemplateEnginesUnitTest extends GroovyTestCase {
+    
+    def bindMap = [user: "Norman", signature: "Baeldung"]
+    
+    void testSimpleTemplateEngine() {
+        def smsTemplate = 'Dear <% print user %>, Thanks for reading our Article. ${signature}'
+        def smsText = new SimpleTemplateEngine().createTemplate(smsTemplate).make(bindMap)
+
+        assert smsText.toString() == "Dear Norman, Thanks for reading our Article. Baeldung"
+    }
+    
+    void testStreamingTemplateEngine() {
+        def articleEmailTemplate = new File('src/main/resources/articleEmail.template')
+        bindMap.articleText = """1. Overview
+This is a tutorial article on Template Engines""" //can be a string larger than 64k
+        
+        def articleEmailText = new StreamingTemplateEngine().createTemplate(articleEmailTemplate).make(bindMap)
+        
+        assert articleEmailText.toString() == """Dear Norman,
+Please read the requested article below.
+1. Overview
+This is a tutorial article on Template Engines
+From,
+Baeldung"""
+        
+    }
+    
+    void testGStringTemplateEngine() {
+        def emailTemplate = new File('src/main/resources/email.template')
+        def emailText = new GStringTemplateEngine().createTemplate(emailTemplate).make(bindMap)
+        
+        assert emailText.toString() == "Dear Norman,\nThanks for subscribing our services.\nBaeldung"
+    }
+    
+    void testXmlTemplateEngine() {
+        def emailXmlTemplate = '''<xs xmlns:gsp='groovy-server-pages'>
+                                      <gsp:scriptlet>def emailContent = "Thanks for subscribing our services."</gsp:scriptlet>
+                                      <email>
+                                          <greet>Dear ${user}</greet>
+                                          <content><gsp:expression>emailContent</gsp:expression></content>
+                                          <signature>${signature}</signature>
+                                      </email>
+                                  </xs>'''
+        def emailXml = new XmlTemplateEngine().createTemplate(emailXmlTemplate).make(bindMap)
+        println emailXml.toString()
+    }
+    
+    void testMarkupTemplateEngineHtml() {
+        def emailHtmlTemplate = """html {
+                                       head {
+                                           title('Service Subscription Email')
+                                       }
+                                       body {
+                                           p('Dear Norman')
+                                           p('Thanks for subscribing our services.')
+                                           p('Baeldung')
+                                       }
+                                   }"""
+        
+        
+        def emailHtml = new MarkupTemplateEngine().createTemplate(emailHtmlTemplate).make()
+        println emailHtml.toString()
+        
+    }
+    
+    void testMarkupTemplateEngineXml() {
+        def emailXmlTemplate = """xmlDeclaration()  
+                                      xs{
+                                          email {
+                                              greet('Dear Norman')
+                                              content('Thanks for subscribing our services.')
+                                              signature('Baeldung')
+                                          }  
+                                      }
+                               """
+        TemplateConfiguration config = new TemplateConfiguration()
+        config.autoIndent = true
+        config.autoEscape = true
+        config.autoNewLine = true
+
+        def emailXml = new MarkupTemplateEngine(config).createTemplate(emailXmlTemplate).make()
+        
+        println emailXml.toString()
+    }
+    
+}