Skip to Content

Wiki source code of WebObjects and Squeryl

Version 147.1 by Ravi Mendis on 2010/11/10 03:20
Show last authors
1 = Squeryl ~= //SQL-like// DSL for Scala =
2
3 Advantages of Squeryl over EOF:
4
5 * Concurrent
6 ** Spawns multiple database connections
7 ** Issues database transactions concurrently
8 * Scala Actor compatible
9 ** Immutable object model/graph
10 * Strongly-typed
11 ** Better suited for database/business "logic".
12 E.g: Exploits the compiler and IDE to catch exceptions at compile time rather than at run-time.
13 * Uses Scala (functional) collection classes
14
15 = Migrating EOF -> Squeryl =
16
17 In keeping with the strong-typed philosophy of Scala, Squeryl has no dynamic component like EOF (i.e an EO model file).
18
19 EOF has the ability to generate classes in Java (and in Objective-C prior to WebObjects 4.5) as enforcing type has become customary in enterprise environments. We may exploit this feature of EOF to generate a Squeryl schema.
20
21 === Preparing your EO model ===
22
23 1. Make sure **all** EO entities have a class name (including abstract many-To-many "join" tables). There's no support for entities marked as ##EOGenericRecord##.
24 1. (Temporary) Ensure all the model entities are in the same package. i.e model <-> package corresponds 1-to-1.
25
26 === Generating the Squeryl Schema ===
27
28 1. Create a .eogen file for your EO model as normal. Only set the ##File Names## extension to "scala".
29 1. Use the Squeryl EO Templates:
30
31 *
32 ** Entity.eotemplate [[template>>WOL:Squeryl _Entity.eotemplate]]
33 ** Entity.eotemplate [[template>>WOL:Squeryl Entity.eotemplate]]
34
35 {{note title="Note"}}
36
37 Any custom business "logic" will have to be manually re-written in Scala
38
39 {{/note}}