sbt.ReflectUtilities.scala Maven / Gradle / Ivy
/* sbt -- Simple Build Tool
* Copyright 2008 David MacIver, Mark Harrah
*/
package sbt
import scala.collection._
object ReflectUtilities {
/** Converts the camelCase String `name` to lowercase separated by `separator`. */
def transformCamelCase(name: String, separator: Char): String =
{
val buffer = new StringBuilder
for (char <- name) {
import java.lang.Character._
if (isUpperCase(char)) {
buffer += separator
buffer += toLowerCase(char)
} else
buffer += char
}
buffer.toString
}
def ancestry(clazz: Class[_]): List[Class[_]] =
if (clazz == classOf[AnyRef] || !classOf[AnyRef].isAssignableFrom(clazz)) List(clazz)
else clazz :: ancestry(clazz.getSuperclass);
def fields(clazz: Class[_]) =
mutable.OpenHashMap(ancestry(clazz).
flatMap(_.getDeclaredFields).
map(f => (f.getName, f)): _*)
/**
* Collects all `val`s of type `T` defined on value `self`.
* The returned Map maps the name of each `val` to its value.
* This depends on scalac implementation details to determine what is a `val` using only Java reflection.
*/
def allValsC[T](self: AnyRef, clazz: Class[T]): immutable.SortedMap[String, T] =
{
var mappings = new immutable.TreeMap[String, T]
val correspondingFields = fields(self.getClass)
for (method <- self.getClass.getMethods) {
if (method.getParameterTypes.isEmpty && clazz.isAssignableFrom(method.getReturnType)) {
for (field <- correspondingFields.get(method.getName) if field.getType == method.getReturnType) {
val value = method.invoke(self).asInstanceOf[T]
if (value == null) throw new UninitializedVal(method.getName, method.getDeclaringClass.getName)
mappings += ((method.getName, value))
}
}
}
mappings
}
/**
* Collects all `val`s of type `T` defined on value `self`.
* The returned Map maps the name of each `val` to its value.
* This requires an available `Manifest` for `T` and depends on scalac implementation details to determine
* what is a `val` using only Java reflection.
*/
def allVals[T](self: AnyRef)(implicit mt: scala.reflect.Manifest[T]): immutable.SortedMap[String, T] =
allValsC(self, mt.runtimeClass).asInstanceOf[immutable.SortedMap[String, T]]
}
/** An exception to indicate that while traversing the `val`s for an instance of `className`, the `val` named `valName` was `null`. */
final class UninitializedVal(val valName: String, val className: String) extends RuntimeException("val " + valName + " in class " + className + " was null.\nThis is probably an initialization problem and a 'lazy val' should be used.")