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Compiler for the Scala Programming Language
package scala.reflect
package runtime
import scala.ref.WeakReference
import scala.collection.mutable.WeakHashMap
import java.lang.{Class => jClass, Package => jPackage}
import java.lang.reflect.{
Method => jMethod, Constructor => jConstructor, Modifier => jModifier, Field => jField,
Member => jMember, Type => jType, TypeVariable => jTypeVariable, Array => jArray,
GenericDeclaration, GenericArrayType, ParameterizedType, WildcardType, AnnotatedElement }
import java.io.IOException
import internal.MissingRequirementError
import internal.pickling.ByteCodecs
import internal.ClassfileConstants._
import internal.pickling.UnPickler
import collection.mutable.{ HashMap, ListBuffer }
import internal.Flags._
//import scala.tools.nsc.util.ScalaClassLoader
//import scala.tools.nsc.util.ScalaClassLoader._
import ReflectionUtils.{singletonInstance}
import language.existentials
trait JavaMirrors extends internal.SymbolTable with api.JavaUniverse { self: SymbolTable =>
private lazy val mirrors = new WeakHashMap[ClassLoader, WeakReference[JavaMirror]]()
private def createMirror(owner: Symbol, cl: ClassLoader): Mirror = {
val jm = new JavaMirror(owner, cl)
mirrors(cl) = new WeakReference(jm)
jm.init()
jm
}
override type RuntimeClass = java.lang.Class[_]
override type Mirror = JavaMirror
override lazy val rootMirror: Mirror = createMirror(NoSymbol, rootClassLoader)
// overriden by ReflectGlobal
def rootClassLoader: ClassLoader = this.getClass.getClassLoader
def init() = {
definitions.AnyValClass // force it.
// establish root association to avoid cyclic dependency errors later
rootMirror.classToScala(classOf[java.lang.Object]).initialize
// println("initializing definitions")
definitions.init()
}
def runtimeMirror(cl: ClassLoader): Mirror = mirrors get cl match {
case Some(WeakReference(m)) => m
case _ => createMirror(rootMirror.RootClass, cl)
}
/** The API of a mirror for a reflective universe */
class JavaMirror(owner: Symbol,
/** Class loader that is a mastermind behind the reflexive mirror */
val classLoader: ClassLoader
) extends Roots(owner) with super.JavaMirror { wholemirror =>
val universe: self.type = self
import definitions._
/** The lazy type for root.
*/
override lazy val rootLoader = new LazyType {
override def complete(sym: Symbol) = sym setInfo new LazyPackageType
}
// ----------- Caching ------------------------------------------------------------------
// [Eugene++ to Martin] not weak? why?
private val classCache = new TwoWayCache[jClass[_], ClassSymbol]
private val packageCache = new TwoWayCache[Package, ModuleSymbol]
private val methodCache = new TwoWayCache[jMethod, MethodSymbol]
private val constructorCache = new TwoWayCache[jConstructor[_], MethodSymbol]
private val fieldCache = new TwoWayCache[jField, TermSymbol]
private val tparamCache = new TwoWayCache[jTypeVariable[_ <: GenericDeclaration], TypeSymbol]
def toScala[J: HasJavaClass, S](cache: TwoWayCache[J, S], key: J)(body: (JavaMirror, J) => S): S =
cache.toScala(key){
val jclazz = implicitly[HasJavaClass[J]] getClazz key
body(mirrorDefining(jclazz), key)
}
private implicit val classHasJavaClass: HasJavaClass[jClass[_]] =
new HasJavaClass(identity)
private implicit val methHasJavaClass: HasJavaClass[jMethod]
= new HasJavaClass(_.getDeclaringClass)
private implicit val fieldHasJavaClass: HasJavaClass[jField] =
new HasJavaClass(_.getDeclaringClass)
private implicit val constrHasJavaClass: HasJavaClass[jConstructor[_]] =
new HasJavaClass(_.getDeclaringClass)
private implicit val tparamHasJavaClass: HasJavaClass[jTypeVariable[_ <: GenericDeclaration]] =
new HasJavaClass ( (tparam: jTypeVariable[_ <: GenericDeclaration]) => {
tparam.getGenericDeclaration match {
case jclazz: jClass[_] => jclazz
case jmeth: jMethod => jmeth.getDeclaringClass
case jconstr: jConstructor[_] => jconstr.getDeclaringClass
}
})
// ----------- Implementations of mirror operations and classes -------------------
def reflect(obj: Any): InstanceMirror = new JavaInstanceMirror(obj.asInstanceOf[AnyRef])
def reflectClass(cls: ClassSymbol): ClassMirror = {
if (!cls.isStatic) throw new Error("this is an inner class, use reflectClass on an InstanceMirror to obtain its ClassMirror")
new JavaClassMirror(null, cls)
}
def reflectModule(mod: ModuleSymbol): ModuleMirror = {
if (!mod.isStatic) throw new Error("this is an inner module, use reflectModule on an InstanceMirror to obtain its ModuleMirror")
new JavaModuleMirror(null, mod)
}
def runtimeClass(tpe: Type): RuntimeClass = typeToJavaClass(tpe)
def runtimeClass(cls: ClassSymbol): RuntimeClass = classToJava(cls)
def classSymbol(rtcls: RuntimeClass): ClassSymbol = classToScala(rtcls)
def moduleSymbol(rtcls: RuntimeClass): ModuleSymbol = classToScala(rtcls).companionModule.asModuleSymbol
private class JavaInstanceMirror(obj: AnyRef)
extends InstanceMirror {
def instance = obj
def symbol = wholemirror.classSymbol(obj.getClass)
def reflectField(field: TermSymbol): FieldMirror = {
// [Eugene+++] check whether `field` represents a member of a `symbol`
if (field.isMethod || field.isModule) throw new Error(s"""
|expected a field symbol, you provided a ${field.kind} symbol
|A typical cause of this problem is using a field accessor symbol instead of a field symbol.
|To obtain a field symbol append nme.LOCAL_SUFFIX_STRING to the name of the field,
|when searching for a member with Type.members or Type.declarations.
|This is a temporary inconvenience that will be resolved before 2.10.0-final.
|More information can be found here: https://issues.scala-lang.org/browse/SI-5895.
""".trim.stripMargin)
new JavaFieldMirror(obj, field)
}
def reflectMethod(method: MethodSymbol): MethodMirror = {
// [Eugene+++] check whether `method` represents a member of a `symbol`
new JavaMethodMirror(obj, method)
}
def reflectClass(cls: ClassSymbol): ClassMirror = {
// [Eugene+++] check whether `cls` represents a member of a `symbol`
if (cls.isStatic) throw new Error("this is a static class, use reflectClass on a RuntimeMirror to obtain its ClassMirror")
new JavaClassMirror(instance, cls)
}
def reflectModule(mod: ModuleSymbol): ModuleMirror = {
// [Eugene+++] check whether `mod` represents a member of a `symbol`
if (mod.isStatic) throw new Error("this is a static module, use reflectModule on a RuntimeMirror to obtain its ModuleMirror")
new JavaModuleMirror(instance, mod)
}
}
private class JavaFieldMirror(val receiver: AnyRef, val symbol: TermSymbol)
extends FieldMirror {
lazy val jfield = {
val jfield = fieldToJava(symbol)
if (!jfield.isAccessible) jfield.setAccessible(true)
jfield
}
def get = jfield.get(receiver)
def set(value: Any) = {
if (!symbol.isMutable) throw new Error("cannot set an immutable field")
jfield.set(receiver, value)
}
}
private class JavaMethodMirror(val receiver: AnyRef, val symbol: MethodSymbol)
extends MethodMirror {
lazy val jmeth = {
val jmeth = methodToJava(symbol)
if (!jmeth.isAccessible) jmeth.setAccessible(true)
jmeth
}
def apply(args: Any*): Any =
if (symbol.owner == ArrayClass)
symbol.name match {
case nme.length => jArray.getLength(receiver)
case nme.apply => jArray.get(receiver, args(0).asInstanceOf[Int])
case nme.update => jArray.set(receiver, args(0).asInstanceOf[Int], args(1))
case _ => throw new Error(s"unexpected array method $symbol")
}
else
jmeth.invoke(receiver, args.asInstanceOf[Seq[AnyRef]]: _*)
}
private class JavaConstructorMirror(val outer: AnyRef, val symbol: MethodSymbol)
extends MethodMirror {
override val receiver = outer
lazy val jconstr = {
val jconstr = constructorToJava(symbol)
if (!jconstr.isAccessible) jconstr.setAccessible(true)
jconstr
}
def apply(args: Any*): Any = {
val effectiveArgs =
if (outer == null) args.asInstanceOf[Seq[AnyRef]]
else outer +: args.asInstanceOf[Seq[AnyRef]]
jconstr.newInstance(effectiveArgs: _*)
}
}
private abstract class JavaTemplateMirror
extends TemplateMirror {
def outer: AnyRef
def erasure: ClassSymbol
lazy val runtimeClass = classToJava(erasure)
lazy val signature = typeToScala(runtimeClass)
}
private class JavaClassMirror(val outer: AnyRef, val symbol: ClassSymbol)
extends JavaTemplateMirror with ClassMirror {
def erasure = symbol
def isStatic = false
def reflectConstructor(constructor: MethodSymbol) = new JavaConstructorMirror(outer, constructor)
def companion: Option[ModuleMirror] = symbol.companionModule match {
case module: ModuleSymbol => Some(new JavaModuleMirror(outer, module))
case _ => None
}
}
private class JavaModuleMirror(val outer: AnyRef, val symbol: ModuleSymbol)
extends JavaTemplateMirror with ModuleMirror {
def erasure = symbol.moduleClass.asClassSymbol
def isStatic = true
def instance = {
if (!symbol.owner.isPackageClass) throw new Error("inner and nested modules are not supported yet")
singletonInstance(classLoader, symbol.fullName)
}
def companion: Option[ClassMirror] = symbol.companionClass match {
case cls: ClassSymbol => Some(new JavaClassMirror(outer, cls))
case _ => None
}
}
// -------------------- Java to Scala -----------------------------------
/** Does method `meth` erase to Java method `jmeth`?
* This is true if the Java method type is the same as the Scala method type after performing
* all Scala-specific transformations in InfoTransformers. (to be done)
*/
private def erasesTo(meth: Symbol, jmeth: jMethod): Boolean = {
val mtpe = transformedType(meth)
(mtpe.paramTypes map runtimeClass) == jmeth.getParameterTypes.toList &&
runtimeClass(mtpe.resultType) == jmeth.getReturnType
}
private def erasesTo(meth: Symbol, jconstr: jConstructor[_]): Boolean = {
val mtpe = transformedType(meth)
(mtpe.paramTypes map runtimeClass) == jconstr.getParameterTypes.toList &&
runtimeClass(mtpe.resultType) == jconstr.getDeclaringClass
}
def javaClass(path: String): jClass[_] =
Class.forName(path, true, classLoader)
/** Does `path` correspond to a Java class with that fully qualified name in the current class loader? */
def tryJavaClass(path: String): Option[jClass[_]] =
try {
Some(javaClass(path))
} catch {
case (_: ClassNotFoundException) | (_: NoClassDefFoundError) | (_: IncompatibleClassChangeError) =>
None
}
/** The mirror that corresponds to the classloader that original defined the given Java class */
def mirrorDefining(jclazz: jClass[_]): JavaMirror = {
val cl = jclazz.getClassLoader
if (cl == this.classLoader) this else runtimeMirror(cl)
}
private object unpickler extends UnPickler {
val global: self.type = self
}
/** how connected????
* Generate types for top-level Scala root class and root companion object
* from the pickled information stored in a corresponding Java class
* @param clazz The top-level Scala class for which info is unpickled
* @param module The top-level Scala companion object for which info is unpickled
* @param jclazz The Java class which contains the unpickled information in a
* ScalaSignature or ScalaLongSignature annotation.
*/
def unpickleClass(clazz: Symbol, module: Symbol, jclazz: jClass[_]): Unit = {
def markAbsent(tpe: Type) = setAllInfos(clazz, module, tpe)
def handleError(ex: Exception) = {
markAbsent(ErrorType)
if (settings.debug.value) ex.printStackTrace()
val msg = ex.getMessage()
MissingRequirementError.signal(
(if (msg eq null) "reflection error while loading " + clazz.name
else "error while loading " + clazz.name) + ", " + msg)
}
// don't use classOf[scala.reflect.ScalaSignature] here, because it will use getClass.getClassLoader, not mirror's classLoader
// don't use asInstanceOf either because of the same reason (lol, I cannot believe I fell for it)
// don't use structural types to simplify reflective invocations because of the same reason
def loadAnnotation(name: String): Option[java.lang.annotation.Annotation] =
tryJavaClass(name) flatMap { annotClass =>
val anns = jclazz.getAnnotations
val result = anns find (_.annotationType == annotClass)
if (result.isEmpty && (anns exists (_.annotationType.getName == name)))
throw new ClassNotFoundException(
s"""Mirror classloader mismatch: $jclazz (loaded by ${ReflectionUtils.show(jclazz.getClassLoader)})
|is unrelated to the mirror's classloader: (${ReflectionUtils.show(classLoader)})""".stripMargin)
result
}
def loadBytes[T: ClassTag](name: String): Option[T] =
loadAnnotation(name) map { ssig =>
val bytesMethod = ssig.annotationType.getMethod("bytes")
bytesMethod.invoke(ssig).asInstanceOf[T]
}
try {
markAbsent(NoType)
loadBytes[String]("scala.reflect.ScalaSignature") match {
case Some(ssig) =>
info(s"unpickling Scala $clazz and $module, owner = ${clazz.owner}")
val bytes = ssig.getBytes
val len = ByteCodecs.decode(bytes)
unpickler.unpickle(bytes take len, 0, clazz, module, jclazz.getName)
case None =>
loadBytes[Array[String]]("scala.reflect.ScalaLongSignature") match {
case Some(slsig) =>
info(s"unpickling Scala $clazz and $module with long Scala signature")
val byteSegments = slsig map (_.getBytes)
val lens = byteSegments map ByteCodecs.decode
val bytes = Array.ofDim[Byte](lens.sum)
var len = 0
for ((bs, l) <- byteSegments zip lens) {
bs.copyToArray(bytes, len, l)
len += l
}
unpickler.unpickle(bytes, 0, clazz, module, jclazz.getName)
case None =>
// class does not have a Scala signature; it's a Java class
info("translating reflection info for Java " + jclazz) //debug
initClassModule(clazz, module, new FromJavaClassCompleter(clazz, module, jclazz))
}
}
} catch {
case ex: MissingRequirementError =>
handleError(ex)
case ex: IOException =>
handleError(ex)
}
}
/**
* A fresh Scala type parameter that corresponds to a Java type variable.
* The association between Scala type parameter and Java type variable is entered in the cache.
* @param jtvar The Java type variable
*/
private def createTypeParameter(jtvar: jTypeVariable[_ <: GenericDeclaration]): TypeSymbol = {
val tparam = sOwner(jtvar).newTypeParameter(newTypeName(jtvar.getName))
.setInfo(new TypeParamCompleter(jtvar))
tparamCache enter (jtvar, tparam)
tparam
}
/**
* A completer that fills in the type of a Scala type parameter from the bounds of a Java type variable.
* @param jtvar The Java type variable
*/
private class TypeParamCompleter(jtvar: jTypeVariable[_ <: GenericDeclaration]) extends LazyType {
override def load(sym: Symbol) = complete(sym)
override def complete(sym: Symbol) = {
sym setInfo TypeBounds.upper(glb(jtvar.getBounds.toList map typeToScala map objToAny))
}
}
/**
* Copy all annotations of Java annotated element `jann` over to Scala symbol `sym`.
* Pre: `sym` is already initialized with a concrete type.
* Note: If `sym` is a method or constructor, its parameter annotations are copied as well.
*/
private def copyAnnotations(sym: Symbol, jann: AnnotatedElement) {
// to do: implement
}
/**
* A completer that fills in the types of a Scala class and its companion object
* by copying corresponding type info from a Java class. This completer is used
* to reflect classes in Scala that do not have a Scala pickle info, be it
* because they are local classes or have been compiled from Java sources.
* @param clazz The Scala class for which info is copied
* @param module The Scala companion object for which info is copied
* @param jclazz The Java class
*/
private class FromJavaClassCompleter(clazz: Symbol, module: Symbol, jclazz: jClass[_]) extends LazyType {
/** used to avoid cycles while initializing classes */
private var parentsLevel = 0
private var pendingLoadActions: List[() => Unit] = Nil
override def load(sym: Symbol): Unit = {
debugInfo("completing from Java " + sym + "/" + clazz.fullName)//debug
assert(sym == clazz || (module != NoSymbol && (sym == module || sym == module.moduleClass)), sym)
val flags = toScalaClassFlags(jclazz.getModifiers)
clazz setFlag (flags | JAVA)
if (module != NoSymbol) {
module setFlag (flags & PRIVATE | JAVA)
module.moduleClass setFlag (flags & PRIVATE | JAVA)
}
copyAnnotations(clazz, jclazz)
// to do: annotations to set also for module?
clazz setInfo new LazyPolyType(jclazz.getTypeParameters.toList map createTypeParameter)
if (module != NoSymbol) {
module setInfo module.moduleClass.tpe
module.moduleClass setInfo new LazyPolyType(List())
}
}
override def complete(sym: Symbol): Unit = {
load(sym)
completeRest()
}
def completeRest(): Unit = self.synchronized {
val tparams = clazz.rawInfo.typeParams
val parents = try {
parentsLevel += 1
val jsuperclazz = jclazz.getGenericSuperclass
val superclazz = if (jsuperclazz == null) AnyClass.tpe else typeToScala(jsuperclazz)
superclazz :: (jclazz.getGenericInterfaces.toList map typeToScala)
} finally {
parentsLevel -= 1
}
clazz setInfo GenPolyType(tparams, new ClassInfoType(parents, newScope, clazz))
if (module != NoSymbol) {
module.moduleClass setInfo new ClassInfoType(List(), newScope, module.moduleClass)
}
def enter(sym: Symbol, mods: Int) =
(if (jModifier.isStatic(mods)) module.moduleClass else clazz).info.decls enter sym
for (jinner <- jclazz.getDeclaredClasses) {
enter(jclassAsScala(jinner, clazz), jinner.getModifiers)
}
pendingLoadActions = { () =>
for (jfield <- jclazz.getDeclaredFields)
enter(jfieldAsScala(jfield), jfield.getModifiers)
for (jmeth <- jclazz.getDeclaredMethods)
enter(jmethodAsScala(jmeth), jmeth.getModifiers)
for (jconstr <- jclazz.getConstructors)
enter(jconstrAsScala(jconstr), jconstr.getModifiers)
} :: pendingLoadActions
if (parentsLevel == 0) {
while (!pendingLoadActions.isEmpty) {
val item = pendingLoadActions.head
pendingLoadActions = pendingLoadActions.tail
item()
}
}
}
class LazyPolyType(override val typeParams: List[Symbol]) extends LazyType {
override def complete(sym: Symbol) {
completeRest()
}
}
}
/**
* If Java modifiers `mods` contain STATIC, return the module class
* of the companion module of `clazz`, otherwise the class `clazz` itself.
*/
private def followStatic(clazz: Symbol, mods: Int) =
if (jModifier.isStatic(mods)) clazz.companionModule.moduleClass else clazz
implicit class RichClass(jclazz: jClass[_]) {
// [Eugene++] `jclazz.isLocalClass` doesn't work because of problems with `getSimpleName`
// java.lang.Error: sOwner(class Test$A$1) has failed
// Caused by: java.lang.InternalError: Malformed class name
// at java.lang.Class.getSimpleName(Class.java:1133)
// at java.lang.Class.isAnonymousClass(Class.java:1188)
// at java.lang.Class.isLocalClass(Class.java:1199)
// (see t5256c.scala for more details)
// hence we have to approximate by removing the `isAnonymousClass` check
// def isLocalClass0: Boolean = jclazz.isLocalClass
def isLocalClass0: Boolean = jclazz.getEnclosingMethod != null || jclazz.getEnclosingConstructor != null
}
// [Eugene++] overflow from Paul's changes made concurrently with reflection refactoring
// https://github.com/scala/scala/commit/90d2bee45b25844f809f8c5300aefcb1bfe9e336
//
// /** Methods which need to be wrapped because they either are getSimpleName
// * or call getSimpleName:
// *
// * public String getSimpleName()
// * public boolean isAnonymousClass()
// * public boolean isLocalClass()
// * public boolean isMemberClass()
// * public String getCanonicalName()
// *
// * TODO - find all such calls and wrap them.
// * TODO - create mechanism to avoid the recurrence of unwrapped calls.
// */
// private def wrapClassCheck[T](alt: T)(body: => T): T =
// try body catch { case x: InternalError if x.getMessage == "Malformed class name" => alt }
// private def wrapIsLocalClass(clazz: jClass[_]): Boolean =
// wrapClassCheck(false)(clazz.isLocalClass)
// private def wrapGetSimpleName(clazz: jClass[_]): String =
// wrapClassCheck("")(clazz.getSimpleName)
/**
* The Scala owner of the Scala class corresponding to the Java class `jclazz`
*/
private def sOwner(jclazz: jClass[_]): Symbol =
if (jclazz.isMemberClass) {
val jEnclosingClass = jclazz.getEnclosingClass
val sEnclosingClass = classToScala(jEnclosingClass)
followStatic(sEnclosingClass, jclazz.getModifiers)
} else if (jclazz.isLocalClass0) {
val jEnclosingMethod = jclazz.getEnclosingMethod
if (jEnclosingMethod != null) {
methodToScala(jEnclosingMethod)
} else {
val jEnclosingConstructor = jclazz.getEnclosingConstructor
constructorToScala(jEnclosingConstructor)
}
} else if (jclazz.isPrimitive || jclazz.isArray) {
ScalaPackageClass
} else if (jclazz.getPackage != null) {
val jPackage = jclazz.getPackage
packageToScala(jPackage).moduleClass
} else {
// @eb: a weird classloader might return a null package for something with a non-empty package name
// for example, http://groups.google.com/group/scala-internals/browse_thread/thread/7be09ff8f67a1e5c
// in that case we could invoke packageNameToScala(jPackageName) and, probably, be okay
// however, I think, it's better to blow up, since weirdness of the class loader might bite us elsewhere
// [martin] I think it's better to be forgiving here. Restoring packageNameToScala.
val jPackageName = jclazz.getName take jclazz.getName.lastIndexOf('.')
packageNameToScala(jPackageName).moduleClass
}
/**
* The Scala owner of the Scala symbol corresponding to the Java member `jmember`
*/
private def sOwner(jmember: jMember): Symbol = {
followStatic(classToScala(jmember.getDeclaringClass), jmember.getModifiers)
}
/**
* The Scala owner of the Scala type parameter corresponding to the Java type variable `jtvar`
*/
private def sOwner(jtvar: jTypeVariable[_ <: GenericDeclaration]): Symbol =
genericDeclarationToScala(jtvar.getGenericDeclaration)
/**
* Find declarations or definition in class `clazz` that maps to a Java
* entity with name `jname`. Because of name-mangling, this is more difficult
* than a simple name-based lookup via `decl`. If `decl` fails, members
* that start with the given name are searched instead.
*/
private def lookup(clazz: Symbol, jname: String): Symbol = {
def approximateMatch(sym: Symbol, jstr: String): Boolean =
(sym.name.toString == jstr) ||
sym.isPrivate && nme.expandedName(sym.name.toTermName, sym.owner).toString == jstr
clazz.info.decl(newTermName(jname)) orElse {
(clazz.info.decls.iterator filter (approximateMatch(_, jname))).toList match {
case List() => NoSymbol
case List(sym) => sym
case alts => clazz.newOverloaded(alts.head.tpe.prefix, alts)
}
}
}
/**
* The Scala method corresponding to given Java method.
* @param jmeth The Java method
* @return A Scala method object that corresponds to `jmeth`.
*/
def methodToScala(jmeth: jMethod): MethodSymbol =
toScala(methodCache, jmeth)(_ methodToScala1 _)
private def methodToScala1(jmeth: jMethod): MethodSymbol = {
val jOwner = jmeth.getDeclaringClass
val preOwner = classToScala(jOwner)
val owner = followStatic(preOwner, jmeth.getModifiers)
(lookup(owner, jmeth.getName) suchThat (erasesTo(_, jmeth)) orElse jmethodAsScala(jmeth))
.asMethodSymbol
}
/**
* The Scala constructor corresponding to given Java constructor.
* @param jconstr The Java constructor
* @return A Scala method object that corresponds to `jconstr`.
*/
def constructorToScala(jconstr: jConstructor[_]): MethodSymbol =
toScala(constructorCache, jconstr)(_ constructorToScala1 _)
private def constructorToScala1(jconstr: jConstructor[_]): MethodSymbol = {
val owner = followStatic(classToScala(jconstr.getDeclaringClass), jconstr.getModifiers)
(lookup(owner, jconstr.getName) suchThat (erasesTo(_, jconstr)) orElse jconstrAsScala(jconstr))
.asMethodSymbol
}
/**
* The Scala field corresponding to given Java field.
* @param jfield The Java field
* @return A Scala field object that corresponds to `jfield`.
* // ??? should we return the getter instead?
*/
def fieldToScala(jfield: jField): TermSymbol =
toScala(fieldCache, jfield)(_ fieldToScala1 _)
private def fieldToScala1(jfield: jField): TermSymbol = {
val owner = followStatic(classToScala(jfield.getDeclaringClass), jfield.getModifiers)
(lookup(owner, jfield.getName) suchThat (!_.isMethod) orElse jfieldAsScala(jfield))
.asTermSymbol
}
/**
* The Scala package corresponding to given Java package
*/
def packageToScala(jpkg: jPackage): ModuleSymbol = packageCache.toScala(jpkg) {
makeScalaPackage(jpkg.getName)
}
/**
* The Scala package with given fully qualified name.
*/
def packageNameToScala(fullname: String): ModuleSymbol = {
if (fullname == "") EmptyPackage
else {
val jpkg = jPackage.getPackage(fullname)
if (jpkg != null) packageToScala(jpkg) else makeScalaPackage(fullname)
}
}
/**
* The Scala package with given fully qualified name. Unlike `packageNameToScala`,
* this one bypasses the cache.
*/
private[JavaMirrors] def makeScalaPackage(fullname: String): ModuleSymbol = {
val split = fullname lastIndexOf '.'
val ownerModule: ModuleSymbol =
if (split > 0) packageNameToScala(fullname take split) else this.RootPackage
val owner = ownerModule.moduleClass
val name = newTermName(fullname drop (split + 1))
val opkg = owner.info decl name
if (opkg.isPackage)
opkg.asModuleSymbol
else if (opkg == NoSymbol) {
val pkg = owner.newPackage(name)
pkg.moduleClass setInfo new LazyPackageType
pkg setInfoAndEnter pkg.moduleClass.tpe
info("made Scala "+pkg)
pkg
} else
throw new ReflectError(opkg+" is not a package")
}
private def scalaSimpleName(jclazz: jClass[_]): TypeName = {
val owner = sOwner(jclazz)
val enclosingClass = jclazz.getEnclosingClass
var prefix = if (enclosingClass != null) enclosingClass.getName else ""
val isObject = owner.isModuleClass && !owner.isPackageClass
if (isObject && !prefix.endsWith(nme.MODULE_SUFFIX_STRING)) prefix += nme.MODULE_SUFFIX_STRING
assert(jclazz.getName.startsWith(prefix))
var name = jclazz.getName.substring(prefix.length)
name = name.substring(name.lastIndexOf(".") + 1)
newTypeName(name)
}
/**
* The Scala class that corresponds to a given Java class.
* @param jclazz The Java class
* @return A Scala class symbol that reflects all elements of the Java class,
* in the form they appear in the Scala pickling info, or, if that is
* not available, wrapped from the Java reflection info.
*/
def classToScala(jclazz: jClass[_]): ClassSymbol =
toScala(classCache, jclazz)(_ classToScala1 _)
private def classToScala1(jclazz: jClass[_]): ClassSymbol = {
val jname = newTypeName(jclazz.getName)
if (jname == fulltpnme.RuntimeNothing) NothingClass
else if (jname == fulltpnme.RuntimeNull) NullClass
else {
val owner = sOwner(jclazz)
val simpleName = scalaSimpleName(jclazz)
def lookupClass = {
def coreLookup(name: Name): Symbol =
owner.info.decl(name) orElse {
if (name.startsWith(nme.NAME_JOIN_STRING)) coreLookup(name drop 1) else NoSymbol
}
if (nme.isModuleName(simpleName))
coreLookup(nme.stripModuleSuffix(simpleName).toTermName) map (_.moduleClass)
else
coreLookup(simpleName)
}
val cls =
if (jclazz.isMemberClass && !nme.isImplClassName(jname))
lookupClass
else if (jclazz.isLocalClass0 || isInvalidClassName(jname))
// local classes and implementation classes not preserved by unpickling - treat as Java
jclassAsScala(jclazz)
else if (jclazz.isArray)
ArrayClass
else
javaTypeToValueClass(jclazz) orElse lookupClass
assert (cls.isType,
s"""${if (cls == NoSymbol) "not a type: symbol" else "no symbol could be"}
| loaded from $jclazz in $owner with name $simpleName and classloader $classLoader""".stripMargin)
cls.asClassSymbol
}
}
/**
* The Scala type parameter that corresponds to a given Java type parameter.
* @param jparam The Java type parameter
* @return A Scala type parameter symbol that has the same owner and name as the Java type parameter
*/
def typeParamToScala(jparam: jTypeVariable[_ <: GenericDeclaration]): TypeSymbol =
toScala(tparamCache, jparam)(_ typeParamToScala1 _)
private def typeParamToScala1(jparam: jTypeVariable[_ <: GenericDeclaration]): TypeSymbol = {
val owner = genericDeclarationToScala(jparam.getGenericDeclaration)
owner.info match {
case PolyType(tparams, _) => tparams.find(_.name.toString == jparam.getName).get.asTypeSymbol
}
}
/**
* The Scala symbol that corresponds to a given Java generic declaration (class, method, or constructor)
*/
def genericDeclarationToScala(jdecl: GenericDeclaration): Symbol = jdecl match {
case jclazz: jClass[_] => classToScala(jclazz)
case jmeth: jMethod => methodToScala(jmeth)
case jconstr: jConstructor[_] => constructorToScala(jconstr)
}
/**
* Given some Java type arguments, a corresponding list of Scala types, plus potentially
* some existentially bound type variables that represent wildcard arguments.
*/
private def targsToScala(owner: Symbol, args: List[jType]): (List[Type], List[TypeSymbol]) = {
val tparams = new ListBuffer[TypeSymbol]
def targToScala(arg: jType): Type = arg match {
case jwild: WildcardType =>
val tparam = owner.newExistential(newTypeName("T$" + tparams.length))
.setInfo(TypeBounds(
lub(jwild.getLowerBounds.toList map typeToScala),
glb(jwild.getUpperBounds.toList map typeToScala map objToAny)))
tparams += tparam
typeRef(NoPrefix, tparam, List())
case _ =>
typeToScala(arg)
}
(args map targToScala, tparams.toList)
}
/**
* The Scala type that corresponds to given Java type
*/
def typeToScala(jtpe: jType): Type = jtpe match {
case jclazz: jClass[_] =>
if (jclazz.isArray)
arrayType(typeToScala(jclazz.getComponentType))
else {
val clazz = classToScala(jclazz)
rawToExistential(typeRef(clazz.owner.thisType, clazz, List()))
}
case japplied: ParameterizedType =>
val (pre, sym) = typeToScala(japplied.getRawType) match {
case ExistentialType(tparams, TypeRef(pre, sym, _)) => (pre, sym)
case TypeRef(pre, sym, _) => (pre, sym)
}
val args0 = japplied.getActualTypeArguments
val (args, bounds) = targsToScala(pre.typeSymbol, args0.toList)
ExistentialType(bounds, typeRef(pre, sym, args))
case jarr: GenericArrayType =>
arrayType(typeToScala(jarr.getGenericComponentType))
case jtvar: jTypeVariable[_] =>
val tparam = typeParamToScala(jtvar)
typeRef(NoPrefix, tparam, List())
}
/**
* The Scala class that corresponds to given Java class without taking
* Scala pickling info into account.
* @param jclazz The Java class
* @return A Scala class symbol that wraps all reflection info of `jclazz`
*/
private def jclassAsScala(jclazz: jClass[_]): Symbol = jclassAsScala(jclazz, sOwner(jclazz))
private def jclassAsScala(jclazz: jClass[_], owner: Symbol): ClassSymbol = {
val name = scalaSimpleName(jclazz)
val completer = (clazz: Symbol, module: Symbol) => new FromJavaClassCompleter(clazz, module, jclazz)
val (clazz, module) = createClassModule(owner, name, completer)
classCache enter (jclazz, clazz)
clazz
}
/**
* The Scala field that corresponds to given Java field without taking
* Scala pickling info into account.
* @param jfield The Java field
* @return A Scala value symbol that wraps all reflection info of `jfield`
*/
private def jfieldAsScala(jfield: jField): TermSymbol =
toScala(fieldCache, jfield)(_ jfieldAsScala1 _)
private def jfieldAsScala1(jfield: jField): TermSymbol = {
val field = sOwner(jfield)
.newValue(newTermName(jfield.getName), NoPosition, toScalaFieldFlags(jfield.getModifiers))
.setInfo(typeToScala(jfield.getGenericType))
fieldCache enter (jfield, field)
copyAnnotations(field, jfield)
field
}
private def setMethType(meth: Symbol, tparams: List[Symbol], paramtpes: List[Type], restpe: Type) = {
meth setInfo GenPolyType(tparams, MethodType(meth.owner.newSyntheticValueParams(paramtpes map objToAny), restpe))
}
/**
* The Scala method that corresponds to given Java method without taking
* Scala pickling info into account.
* @param jmeth The Java method
* @return A Scala method symbol that wraps all reflection info of `jmethod`
*/
private def jmethodAsScala(jmeth: jMethod): MethodSymbol =
toScala(methodCache, jmeth)(_ jmethodAsScala1 _)
private def jmethodAsScala1(jmeth: jMethod): MethodSymbol = {
val clazz = sOwner(jmeth)
val meth = clazz.newMethod(newTermName(jmeth.getName), NoPosition, toScalaMethodFlags(jmeth.getModifiers))
methodCache enter (jmeth, meth)
val tparams = jmeth.getTypeParameters.toList map createTypeParameter
val paramtpes = jmeth.getGenericParameterTypes.toList map typeToScala
val resulttpe = typeToScala(jmeth.getGenericReturnType)
setMethType(meth, tparams, paramtpes, resulttpe)
copyAnnotations(meth, jmeth)
if ((jmeth.getModifiers & JAVA_ACC_VARARGS) != 0) meth.setInfo(arrayToRepeated(meth.info))
meth
}
/**
* The Scala constructor that corresponds to given Java constructor without taking
* Scala pickling info into account.
* @param jconstr The Java constructor
* @return A Scala constructor symbol that wraps all reflection info of `jconstr`
*/
private def jconstrAsScala(jconstr: jConstructor[_]): MethodSymbol =
toScala(constructorCache, jconstr)(_ jconstrAsScala1 _)
private def jconstrAsScala1(jconstr: jConstructor[_]): MethodSymbol = {
// [Martin] Note: I know there's a lot of duplication wrt jmethodAsScala, but don't think it's worth it to factor this out.
val clazz = sOwner(jconstr)
val constr = clazz.newConstructor(NoPosition, toScalaMethodFlags(jconstr.getModifiers))
constructorCache enter (jconstr, constr)
val tparams = jconstr.getTypeParameters.toList map createTypeParameter
val paramtpes = jconstr.getGenericParameterTypes.toList map typeToScala
setMethType(constr, tparams, paramtpes, clazz.tpe)
constr setInfo GenPolyType(tparams, MethodType(clazz.newSyntheticValueParams(paramtpes), clazz.tpe))
copyAnnotations(constr, jconstr)
constr
}
// -------------------- Scala to Java -----------------------------------
/** Optionally, the Java package corresponding to a given Scala package, or None if no such Java package exists.
* @param pkg The Scala package
*/
def packageToJavaOption(pkg: ModuleSymbol): Option[jPackage] = packageCache.toJavaOption(pkg) {
Option(jPackage.getPackage(pkg.fullName.toString))
}
/** The Java class corresponding to given Scala class.
* Note: This only works for
* - top-level classes
* - Scala classes that were generated via jclassToScala
* - classes that have a class owner that has a corresponding Java class
* @throws A `ClassNotFoundException` for all Scala classes not in one of these categories.
*/
@throws(classOf[ClassNotFoundException])
def classToJava(clazz: ClassSymbol): jClass[_] = classCache.toJava(clazz) {
def noClass = throw new ClassNotFoundException("no Java class corresponding to "+clazz+" found")
//println("classToJava "+clazz+" "+clazz.owner+" "+clazz.owner.isPackageClass)//debug
if (clazz.isPrimitiveValueClass)
valueClassToJavaType(clazz)
else if (clazz == ArrayClass)
noClass
else if (clazz.owner.isPackageClass)
javaClass(clazz.javaClassName)
else if (clazz.owner.isClass)
classToJava(clazz.owner.asClassSymbol)
.getDeclaredClasses
.find(_.getSimpleName == clazz.name.toString)
.getOrElse(noClass)
else
noClass
}
private def expandedName(sym: Symbol): String =
if (sym.isPrivate) nme.expandedName(sym.name.toTermName, sym.owner).toString
else sym.name.toString
/** The Java field corresponding to a given Scala field.
* @param meth The Scala field.
*/
def fieldToJava(fld: TermSymbol): jField = fieldCache.toJava(fld) {
val jclazz = classToJava(fld.owner.asClassSymbol)
val jname = nme.dropLocalSuffix(fld.name).toString
try jclazz getDeclaredField jname
catch {
case ex: NoSuchFieldException => jclazz getDeclaredField expandedName(fld)
}
}
/** The Java method corresponding to a given Scala method.
* @param meth The Scala method
*/
def methodToJava(meth: MethodSymbol): jMethod = methodCache.toJava(meth) {
val jclazz = classToJava(meth.owner.asClassSymbol)
val paramClasses = transformedType(meth).paramTypes map typeToJavaClass
val jname = nme.dropLocalSuffix(meth.name).toString
try jclazz getDeclaredMethod (jname, paramClasses: _*)
catch {
case ex: NoSuchMethodException =>
jclazz getDeclaredMethod (expandedName(meth), paramClasses: _*)
}
}
/** The Java constructor corresponding to a given Scala constructor.
* @param constr The Scala constructor
*/
def constructorToJava(constr: MethodSymbol): jConstructor[_] = constructorCache.toJava(constr) {
val jclazz = classToJava(constr.owner.asClassSymbol)
val paramClasses = transformedType(constr).paramTypes map typeToJavaClass
val effectiveParamClasses =
if (!constr.owner.owner.isStaticOwner) jclazz.getEnclosingClass +: paramClasses
else paramClasses
jclazz getConstructor (effectiveParamClasses: _*)
}
private def jArrayClass(elemClazz: jClass[_]): jClass[_] = {
jArray.newInstance(elemClazz, 0).getClass
}
/** The Java class that corresponds to given Scala type.
* Pre: Scala type is already transformed to Java level.
*/
def typeToJavaClass(tpe: Type): jClass[_] = tpe match {
case ExistentialType(_, rtpe) => typeToJavaClass(rtpe)
case TypeRef(_, ArrayClass, List(elemtpe)) => jArrayClass(typeToJavaClass(elemtpe))
case TypeRef(_, sym: ClassSymbol, _) => classToJava(sym.asClassSymbol)
case _ => throw new NoClassDefFoundError("no Java class corresponding to "+tpe+" found")
}
}
/** Assert that packages have package scopes */
override def validateClassInfo(tp: ClassInfoType) {
assert(!tp.typeSymbol.isPackageClass || tp.decls.isInstanceOf[PackageScope])
}
override def newPackageScope(pkgClass: Symbol) = new PackageScope(pkgClass)
override def scopeTransform(owner: Symbol)(op: => Scope): Scope =
if (owner.isPackageClass) owner.info.decls else op
private lazy val rootToLoader = new WeakHashMap[Symbol, ClassLoader]
override def mirrorThatLoaded(sym: Symbol): Mirror = {
val root = sym.enclosingRootClass
def findLoader = {
val loaders = (mirrors collect { case (cl, ref) if ref.get.get.RootClass == root => cl })
assert(loaders.nonEmpty, sym)
loaders.head
}
mirrors(rootToLoader getOrElseUpdate(root, findLoader)).get.get
}
private def byName(sym: Symbol): (Name, Symbol) = sym.name -> sym
private lazy val phantomTypes: Map[Name, Symbol] =
Map(byName(definitions.AnyRefClass)) ++ (definitions.isPhantomClass map byName)
/** 1. If `owner` is a package class (but not the empty package) and `name` is a term name, make a new package
* ., otherwise return NoSymbol.
* Exception: If owner is root and a java class with given name exists, create symbol in empty package instead
* 2. If `owner` is the scala package and `name` designates a phantom class, return
* the corresponding class symbol and enter it into this mirror's ScalaPackage.
*/
override def missingHook(owner: Symbol, name: Name): Symbol = {
if (owner.hasPackageFlag) {
val mirror = mirrorThatLoaded(owner)
// [Eugene++] this makes toolbox tests pass, but it's a mere workaround for SI-5865
// assert((owner.info decl name) == NoSymbol, s"already exists: $owner . $name")
if (owner.isRootSymbol && mirror.tryJavaClass(name.toString).isDefined)
return mirror.EmptyPackageClass.info decl name
if (name.isTermName && !owner.isEmptyPackageClass)
return mirror.makeScalaPackage(
if (owner.isRootSymbol) name.toString else owner.fullName+"."+name)
if (owner.name.toTermName == nme.scala_ && owner.owner.isRoot)
phantomTypes get name match {
case Some(tsym) =>
owner.info.decls enter tsym
return tsym
case None =>
}
}
info("*** missing: "+name+"/"+name.isTermName+"/"+owner+"/"+owner.hasPackageFlag+"/"+owner.info.decls.getClass)
super.missingHook(owner, name)
}
}
class ReflectError(msg: String) extends java.lang.Error(msg)
class HasJavaClass[J](val getClazz: J => java.lang.Class[_])