Read Nested List from Database with relation and Create another List using Scala Recursivly

Question

![enter image description here][1]I have class as it is defined bellow and I read the database fill the records with TbMenu List of TbMenu will be generated.

TbMenu is having its Children list pointing to Parent Id

case class TbMenu(Name:String,Url:String,Children:List[TbMenu]) - Squeryl Database case class

I want to write method to Read above structure recursively and create another list of of object according to following structure

case class MenuBO(Name:String,Url:String,Children:List[TbMenuBO])

It will be really great help to give me some sample implementation of above.

def GenerateMenuData( orgData: List[TbMenu]): List[MenuBO] = { val list: List[MenuBO] = Nil def helper(orgData:List[TbMenu], result:List[MenuBO]): List[MenuBO] = { orgData match{ case x :: tail => { val Menu = new MenuBO(x.id, x.Description, x.ParentId, x.Url, x.haschildren, null) x.children.toList match{ case x:: tail =>{ val Menu2 = new MenuBO(x.id, x.Description, x.ParentId, x.Url, x.haschildren, null) helper(tail, result ::: List(Menu2)) } case Nil => return result} Menu.Children=result helper(tail, result ::: List(Menu)) }case Nil => result }} helper(orgData,list) }

Thank you in advance

TbMenuBO is a Business object that is used to draw menu in UI layer with play framework after filling it from TbMenu at the service layer — Bimal Kaluarachchi
TbMenu used to retrive data from Squeryl Database it has self relation defined to it self like parent child relation ship — Bimal Kaluarachchi
My question was about TbMenuBO, a list of which you are storing in class MenuBO. — David Frank

David Frank David Frank · Accepted Answer · 2015-01-08T00:38:52

Assuming that TbMenuBO is the same as MenuBO, the solution can be the following:

def Read(menu: TbMenu): MenuBO = {
  menu match {
    case TbMenu(name, url, children) => MenuBO(name, url, children.map(Read))
  }
}

I suggest you adhering to the official coding conventions (method names and field names should start with lower case characters).

Read Nested List from Database with relation and Create another List using Scala Recursivly

1 Answers