Scala example source code file (Analysis.scala)

This example Scala source code file (Analysis.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

analysis, array, array, dirbasedcategory, file, javaclassloader, net, network, path, path, reflection, scalap, scalap, scalaptest, string, string

The Scala Analysis.scala source code

/* NEST (New Scala Test)
 * Copyright 2007-2011 LAMP/EPFL
 */

package scala.tools
package partest
package category

import java.lang.{ ClassLoader => JavaClassLoader }
import java.net.URL
import nsc.util.ScalaClassLoader
import nsc.io._

class PartestClassLoader(urls: Array[URL], parent: JavaClassLoader) extends ScalaClassLoader.URLClassLoader(urls, parent) {
  def this(urls: Array[URL])  = this(urls, null)
  def bytes(path: String)     = findBytesForClassName(path)
  def singleton(path: String) = tryToInitializeClass(path).get getField "MODULE$" get null

  /** Calls a method in an object via reflection.
   */
  def apply[T](className: String, methodName: String)(args: Any*): T = {
    def fail = error("Reflection failed on %s.%s".format(className, methodName))
    val clazz = tryToLoadClass(className) getOrElse fail
    val obj = singleton(className)
    val m = clazz.getMethods find (x => x.getName == methodName && x.getParameterTypes.size == args.size) getOrElse fail

    m.invoke(obj, args map (_.asInstanceOf[AnyRef]): _*).asInstanceOf[T]
  }
}

trait Analysis {
  self: Universe =>
  
  object Scalap extends DirBasedCategory("scalap") {
    val testSequence: TestSequence = List(checkFileRequired, compile, run, diff)
    override def denotesTest(p: Path) = p.isDirectory && (p.toDirectory.files exists (_.name == "result.test"))
    override def createTest(location: Path) = new ScalapTest(location)
    
    class ScalapTest(val location: Path) extends TestEntity {
      val category      = Scalap
      val scalapMain    = "scala.tools.scalap.Main$"
      val scalapMethod  = "decompileScala"

      override def classpathPaths = super.classpathPaths :+ build.scalap
      override def checkFile      = File(location / "result.test")

      private def runnerURLs        = build.classpathPaths ::: classpathPaths map (_.toURL)
      private def createClassLoader = new PartestClassLoader(runnerURLs.toArray, this.getClass.getClassLoader)
      
      val isPackageObject = containsString("package object")
      val suffix          = if (isPackageObject) ".package" else ""
      val className       = location.name.capitalize + suffix

      override def run() = loggingResult {
        def loader  = createClassLoader
        def bytes   = loader.bytes(className)
        
        trace("scalap %s".format(className))
        if (isDryRun) ""
        else loader[String](scalapMain, scalapMethod)(bytes, isPackageObject)
      }
    }
  }
}