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Wiki source code of WebObjects with Scala

Version 25.1 by Ravi Mendis on 2009/09/15 20:38
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1 === What is Scala? ===
2
3 Scala is a modern language not unlike Groovy.
4 It is said to be more powerful (and faster) than Groovy or Rails which has been the reason for its adoption at sites like Twitter.
5
6 Many of its features and paradigms favor multi-threaded and concurrent development:
7
8 |= |= Objective-C |= Java |= Scala
9 |= Mutable/Immuable Datatypes |Collections (e.g: //NSArray/NSMutableArray//) | No | //All datatypes//
10 |= Closures | (//extensions//) | No | //Built-in//
11 |= Static variables | Yes | Yes | No
12 |= Static methods/functions | Yes | Yes | No
13 |= Concurrency | Grand Central Dispatch (//extensions//) | //Threads// | Actors
14
15 Other notable features include:
16
17 |= |= Objective-C |= Java |= Scala
18 |= Parametered methods | Yes (e.g: //addObject: to:_) //| No | Yes (e.g: //add(object= ,to=)//
19 |= Class composition | Categories | Interfaces | Traits
20
21 === Why Use Scala? ===
22
23 With Web 2.0, building concurrent WebObjects applications is a must.
24 Developing and maintaining a concurrent or multi-threaded WebObjects application can be challenging.
25
26 Scala offers concurrency built into the language.
27 So it may offer new solutions to allowing concurrency in WebObjects.
28
29 === Can WebObjects be Programmed With Scala? ===
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31 Yes. It is very simple.
32 Scala compiles to java bytecode. Hence using it with WebObjects is fairly straightforward.
33
34 == How to Develop WebObjects With Scala ==
35
36 1. [[Install the Scala eclipse IDE>>http://www.scala-lang.org/node/94]]
37 1. Add Scala support to your project
38 11. Right-click your project in the WO Explorer
39 11. In the context menu select Scala -> Add Scala Nature
40 1. Convert or use ##.scala## instead of ##.java## source
41
42 {{note title="Note"}}
43
44 This is for Eclipse/WOLips developers
45
46 {{/note}}
47
48 == WO Scala Example ==
49
50 The following is a mixed Java/Scala version of the WO Movies D2W app.
51 All the EO logic and WO components are in Scala.
52 Only the Application class is Java.
53
54 {{attachments patterns=".*zip"}}{{/attachments}}
55
56 === Setup ===
57
58 1. Install and run the OpenBase OBMovies database.
59 1. Right-click on Application.java and run as a WOApplication (as usual).
60
61 ==== EO Templates ====
62
63 See: [[Scala templates>>http://wiki.objectstyle.org/confluence/display/WOL/EOGenerator+Templates+and+Additions]]