input templated XML file and replace the placeholders with random strings of specific length

gistfile1.txt

import groovy.text.GStringTemplateEngine

def engine = new GStringTemplateEngine()

def pool = ['a'..'z','A'..'Z',0..9,'_'].flatten()
Random rand = new Random(System.currentTimeMillis())

def orderidChars = (0..10).collect { pool[rand.nextInt(pool.size())] }
def order_id = orderidChars.join()
vars.put("order_id", "T_"+order_id)

def customeremailidlist = vars.getObject("customeremailidlist")
def email_id = customeremailidlist[rand.nextInt(customeremailidlist.size())]
vars.put("EMAIL_ID", email_id)

String fileContents = new File('${SCRIPT_PATH}/data/German.xml').getText('UTF-8')
def replacements = [EMAIL_ID:email_id, order_id:"T_"+order_id]
def template = engine.createTemplate(fileContents).make(replacements)

vars.put('FILE_CONTENT', template.toString())