Spring & Velocity at log4p

Spring & Velocity

Published by peter January 17th, 2006 in java.

Brainstorming a bit on creating e-mail templates I remembered I had seen people use Velocity to do this. Together with Spring it seemed ideal for the job!

So, to see how Spring and Velocity fit together I mocked up a some test:

first, setup the application context:





“http://www.springframework.org/dtd/spring-beans.dtd”>




velocity/

Then, create a simple unit test (well, technically, provide the meanse to execute) to run:


package com.finalist.velo;
import java.util.HashMap;

import java.util.Map;
import org.apache.velocity.app.VelocityEngine;

import org.apache.velocity.exception.VelocityException;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import org.springframework.ui.velocity.VelocityEngineUtils;
import junit.framework.TestCase;
public class VelocityTest extends TestCase {

private ApplicationContext ctx = null;

private VelocityEngine ve = null;
protected void setUp() throws Exception {

String[] paths = { “applicationContext.xml” };

ctx = new ClassPathXmlApplicationContext(paths);

ve = (VelocityEngine) ctx.getBean(”velocityEngine”);

}
public void testSimpleTemplate(){

try {

Map properties = new HashMap();

properties.put(”name”,”peter”);

properties.put(”array”,new String[]{”one”,”two”,”three”});

properties.put(”testBean”,new TestBean(”property a”,new Integer(123))); // simple bean with 2 properties
String result = VelocityEngineUtils.mergeTemplateIntoString(ve,”simple.vm”,properties);

System.out.println(result);

}

catch (VelocityException e) {

e.printStackTrace();

}

}

}

Create a simple template, and put in ${classpath}/velocity as defined by the ‘resourceLoaderPath’ property in the applicationContext config:


My name is $name
#foreach( $item in $array )

* $item

#end
alle items, behalve element “two”
#foreach( $item in $array )

#if( $item != “two”)

* $item

#end

#end
bean property (String) $testBean.a from $testBean.class.name

bean property (Integer) $testBean.b from $testBean.class.name

And: instant gratification:


My name is peter
* one

* two

* three
alle items, behalve element “two”
* one

* three
bean property (String) property a from com.finalist.velo.TestBean

bean property (Integer) 123 from com.finalist.velo.TestBean

Seems really fit for the email templating I had in mind!