Hi,
The report is a bit different this week because my intention was to load the
scala Interpreter in sling.
I tried to fix the scala interpreter loading problem this week. This is the
most important thing in sling-scala.
In doing so I found that the Scala Interpreter is a special case of the
compiler.[1]
That means a wrapper to the compiler.
The compiler has to be notified the classpath location to the
scala-library-2.7.1.jar or other scala-library jar version.
This should be done by passing it using the scala.tools.nsc.Settings object.
If the classpath is not specified Interpreter will look in the paths it
guesses as in [2].
I tried the following and different variations of them but failed,
1. Inside the engine I tried the solution suggested by Felix using
ClassLoader.currentTheread().
2. loading "scala.tools.nsc.Interpreter" using
ClassLoader.loadClass("scala.tools.nsc.Interpreter") which returns null.
3. Reading the URL of the parent class loaders which doesn't go beyond
"felix://extensions/" I passed this to the Settings.
4. Using the <Import-package> and <Private-Package> directives in maven.
These help compiling but doesn't include the scala-library to the current
class path.
5. The "maven-scala-plugin" is only able to compile and run scala code using
the "compile" , "testcompile". There is no "install" goal. This requires
.scala files. Even though java code can be run in scala I think scala byte
code cannot be run in the jvm. Although I tried to change the extension
there were syntax errors because the plugin expects scala syntax for
methods.
6. Tried to write a dummy class in scala which creates the interpreter and
passes it the Setting without absolute path and pass it the script string
within eval method.
As the bundle ID reads I have tried these a 184 times.
My suggested solution,
1. While compiling in maven copy the
"m2/repository/org/scala-lang/scala-library/2.7.1/scala-library-2.7.1.jar"
in to a directory in target/lib and create a plain file with the version.
Then possible to give the classpath as "/lib/scala-library"+ version +
"jar".
I don't know whether it's possible in maven or how it's done if possible.
2. Create an osgi bundle using the existing maven dependancy "scala-library"
in repository to include it in "apache felix". This might help in solving
the problem but I don't know the correct way to do it. According to what I
found in google it's possible to create osgi bundles in scala code and
compile using the "maven-scala-plugin" but what I want is to wrap the
scla-library as a bundle to load in sling while building using maven..
3. Setting an environment variable to the maven repository and get the
classpath using
"org/scala-lang/scala-library/2.7.1/scala-library-2.7.1.jar".
I'm currently confused with this problem. I can write tests for the current
code but even though all other code is completed using
"Settings.classpath().value_$eq("/home/janandith/.m2/repository/org/scala-lang/scala-library/2.7.1/scala-library-2.7.1.jar");"
temporarily it would leave with the same problem of avoiding path setting in
the completed project.
What are your suggesstions ?. How can I move forward in solving this issue.
[1]
https://lampsvn.epfl.ch/trac/scala/browser/scala/trunk/src/compiler/scala/tools/nsc/Interpreter.scala
[2]
https://lampsvn.epfl.ch/trac/scala/browser/scala/trunk/src/compiler/scala/tools/nsc/Settings.scala
