All custom codec must be in grails-app/utils folder in any package. Suppose I first created a package named 'pritom.kumar.codecs'. Then created a groovy (not other type of class) class inside the package such named 'UpperCodec'.groovy Class name must be end with 'Codec'. My custom codec groovy class look like this:
package pritom.kumar.codecs /** * Created by pritom on 05/09/2014. */ class UpperCodec { static encode = { target -> return target != null && target instanceof String ? target.toString().toUpperCase() : target } }
Now you can use this as code in controller, service, other java or groovy classes, views and other places like this. println "i am pritom kumar".encodeAsUpper(); Will print the following: I AM PRITOM KUMAR Basically you can do various things using custom codec.