Scala on Google App Engine
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"Absorbing Scala into Java Ecosystem"
Google App Engine
Run your web apps on Google's infrastructure.
Easy to build, easy to maintain, easy to scale.
Now with Java
And a host of languages that run on the JVM
JRuby, Groovy, Scala, Jython, ...
Great GAE support for Java with GWT and JDO
Some problems coming to Scala
All you need
Longer development/test cycle
Scala and Google Web Toolkit (GWT)
GWT - quickly build and maintain complex & performant
GWT actually compiles the Java source code
A GWT class should not reference any Scala class
Still, GWT is super cool, use it!
You can still have 99% of the server side in Scala
Use Java only for service interfaces
Use Scala for the rest
To buffer between Scala and GWT code
Scala @ JDO: Spelling it out
Similar to the Java JDO
Using the same annotations
Scala @ JDO: ANT
The ORM enhancer works on the class files
Does not matter if its Java or Scala
Scala @ JDO: Eclipse Support
Not really working since the IDE is looking for Java
source files to instrument
The solution is to use Eclipse Builders
Have the ANT JDO builder building after compilation
Provide an appengine.sdk path to the jar Eclipse use
Same limitations as in Java
Can't open new threads => Actors in a same thread mode
Lift on a single threaded Actor is happy
how to read
java code !