So during a recent exercise at work to prototype some currently functionality from Java/JSP to Scala/Lift we needed to support loading some beans from the spring context and support lists; two things that we were intimately familiar with in Java but were lost in the weeds with in Lift.  We found that it was relatively simple, but it took a while to come to that conclusion.  Here is what we ended up doing.

First we created a helper class to load the context from Spring which turned out to be as simple as the following:

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package hsr.model
import net.liftweb.http.{LiftRules, S, SHtml}
import org.springframework.web.context.ContextLoader
import com.demo.app.icue.helloworld.businesslogic.HelloWorld
import com.demo.app.common.reference.businesslogic.Reference
import org.springframework.validation.{MapBindingResult,BindingResult,FieldError,ObjectError}

/**
 * Some utils for integrating Lift and Spring.
 * http://wordpress.rintcius.nl/post/a-recipe-to-integrate-lift-in-an-existing-spring-based-web-application
 * http://camel.465427.n5.nabble.com/Scala-and-Spring-config-td474898.html
 * http://berlinbrowndev.blogspot.com/2008/02/accessing-spring-framework-from-liftweb.html
 */
object LiftUtils {
 val context = ContextLoader.getCurrentWebApplicationContext()
 def getHelloWorld: HelloWorld = context.getBean("com.demo.app.icue.helloworld.businesslogic.HelloWorld").asInstanceOf[HelloWorld]
 def getReference: Reference = context.getBean("com.demo.app.common.reference.businesslogic.Reference").asInstanceOf[Reference]
}

The places we found some sample code from are listed in the object javadoc. Essentially this is loading the [Class]Impl files from the spring context.  So in this case it loads HelloWorldImpl and ReferenceImpl.

For the next set of code we have a method to turn the List from the ReferenceImpl into a Map so we can use it more efficiently in Scala.  We first call the getReference and load up a list of pojo objects from the database.  We then convert the list into buffer, convert the buffer to a list and iterate over it and create a map that contains just the data we wanted for our demonstration.  This code could certainly be condensed more.  We were unsure when we wrote this prototype of going through the conversion of Java.List –> Buffer –> Scala.List-> Map was the best approach for this, but it worked and it served the purpose for the prototype and might be useful for more people in the future.  Cheers!

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def getReference(referenceName: String) = {
 val values = scala.collection.JavaConversions.asBuffer(LiftUtils.getReference.list(referenceName))
 values.toList.map(v => (v.getReferenceCode, v.getReferenceDesc))
 }