diff options
Diffstat (limited to 'src/compiler/scala/reflect/runtime/JavaToScala.scala')
| -rw-r--r-- | src/compiler/scala/reflect/runtime/JavaToScala.scala | 209 |
1 files changed, 152 insertions, 57 deletions
diff --git a/src/compiler/scala/reflect/runtime/JavaToScala.scala b/src/compiler/scala/reflect/runtime/JavaToScala.scala index 89fd6bab64..6688d77985 100644 --- a/src/compiler/scala/reflect/runtime/JavaToScala.scala +++ b/src/compiler/scala/reflect/runtime/JavaToScala.scala @@ -34,16 +34,42 @@ trait JavaToScala extends ConversionUtil { self: SymbolTable => val global: JavaToScala.this.type = self } - protected def defaultReflectiveClassLoader(): JClassLoader = { - val cl = Thread.currentThread.getContextClassLoader - if (cl == null) getClass.getClassLoader else cl - } + /** Defines the classloader that will be used for all class resolution activities in this mirror. + * Is mutable, since sometimes we need to change it in flight (e.g. to make the default mirror work with REPL). + * + * If you want to have a mirror with non-standard class resolution, override this var + * (or, even simpler, use the `mkMirror` function from `scala.reflect` package) + * + * Be careful, though, since fancy stuff might happen. + * Here's one example: + * + * partest uses a URLClassLoader(urls, null) with custom classpath to run workers (in separate threads) + * however it doesn't set the context classloader for them, so they inherit the system classloader + * http://www.javaworld.com/javaworld/javaqa/2003-06/01-qa-0606-load.html + * + * Once upon a time, scala.reflect.mirror was loaded using getClass.getClassLoader, + * which also means that classOf[...] constructs such as: + * + * classOf[scala.reflect.ScalaSignature] + * + * in unpickleClass were also loaded by the URLClassLoader + * + * But mirror's classLoader used Thread.currentThread.getContextClassLoader, + * which introduced a subtle bug that made the following snippet incorrectly: + * + * jclazz.getAnnotation(classOf[scala.reflect.ScalaSignature]) + * + * Indeed, jclazz was loaded by context classloader, which defaulted to system classloader, + * while ScalaSignature class was loaded by getClass.getClassLoader, which was incompatible with system classloader. + * As a result, unpickler couldn't see the signature and that blew up the mirror. + */ + var classLoader: ClassLoader /** Paul: It seems the default class loader does not pick up root classes, whereas the system classloader does. * Can you check with your newly acquired classloader fu whether this implementation makes sense? */ def javaClass(path: String): jClass[_] = - javaClass(path, defaultReflectiveClassLoader()) + javaClass(path, classLoader) def javaClass(path: String, classLoader: JClassLoader): jClass[_] = Class.forName(path, true, classLoader) @@ -75,19 +101,70 @@ trait JavaToScala extends ConversionUtil { self: SymbolTable => (if (msg eq null) "reflection error while loading " + clazz.name else "error while loading " + clazz.name) + ", " + msg) } - try { - markAbsent(NoType) - val ssig = jclazz.getAnnotation(classOf[scala.reflect.ScalaSignature]) + // 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 + // todo. test for this + def loadAnnotation(name: String): java.lang.annotation.Annotation = { + def inferClasspath(cl: ClassLoader) = cl match { + case cl: java.net.URLClassLoader => "[" + (cl.getURLs mkString ",") + "]" + case _ => "<unknown>" + } + def show(cl: ClassLoader) = cl match { + case cl if cl != null => + "%s of type %s with classpath %s".format(cl, cl.getClass, inferClasspath(cl)) + case null => + import scala.tools.util.PathResolver.Environment._ + "primordial classloader with boot classpath [%s]".format(javaBootClassPath) + } + + try { + val cls_ann = Class.forName(name, true, classLoader) + val anns = jclazz.getAnnotations + val ann = anns find (_.annotationType == cls_ann) orNull; + if (ann == null && anns.find(_.annotationType.getName == name).isDefined) { + val msg = "Mirror classloader mismatch: %s (loaded by %s)%nis unrelated to the mirror's classloader (%s)" + throw new Error(msg.format(jclazz, show(jclazz.getClassLoader), show(classLoader))) + } + ann + } catch { + case ex: ClassNotFoundException => + val msg = "Dysfunctional mirror classloader, cannot load %s: %s." + throw new Error(msg.format(name, show(classLoader)), ex) + } + } + def loadScalaSignature: Option[String] = { + val ssig = loadAnnotation("scala.reflect.ScalaSignature") if (ssig != null) { - info("unpickling Scala "+clazz + " and " + module+ ", owner = " + clazz.owner) - val bytes = ssig.bytes.getBytes - val len = ByteCodecs.decode(bytes) - unpickler.unpickle(bytes take len, 0, clazz, module, jclazz.getName) + val bytesMethod = ssig.annotationType.getMethod("bytes") + val result = bytesMethod.invoke(ssig) + Some(result.asInstanceOf[String]) } else { - val slsig = jclazz.getAnnotation(classOf[scala.reflect.ScalaLongSignature]) - if (slsig != null) { + None + } + } + def loadScalaLongSignature: Option[Array[String]] = { + val slsig = loadAnnotation("scala.reflect.ScalaLongSignature") + if (slsig != null) { + val bytesMethod = slsig.annotationType.getMethod("bytes") + val result = bytesMethod.invoke(slsig) + Some(result.asInstanceOf[Array[String]]) + } else { + None + } + } + try { + markAbsent(NoType) + val sigs = (loadScalaSignature, loadScalaLongSignature) + sigs match { + case (Some(ssig), _) => + info("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 (_, Some(slsig)) => info("unpickling Scala "+clazz + " and " + module + " with long Scala signature") - val byteSegments = slsig.bytes map (_.getBytes) + val byteSegments = slsig map (_.getBytes) val lens = byteSegments map ByteCodecs.decode val bytes = Array.ofDim[Byte](lens.sum) var len = 0 @@ -96,10 +173,10 @@ trait JavaToScala extends ConversionUtil { self: SymbolTable => len += l } unpickler.unpickle(bytes, 0, clazz, module, jclazz.getName) - } else { // class does not have a Scala signature; it's a Java class + case (None, 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 => @@ -383,52 +460,70 @@ trait JavaToScala extends ConversionUtil { self: SymbolTable => */ def classToScala(jclazz: jClass[_]): Symbol = classCache.toScala(jclazz) { val jname = javaTypeName(jclazz) - val owner = sOwner(jclazz) - val simpleName = scalaSimpleName(jclazz) - - val sym = { - def lookup = { - def coreLookup(name: Name): Symbol = { - val sym = owner.info.decl(name) - sym orElse { - if (name.startsWith(nme.NAME_JOIN_STRING)) - coreLookup(name.subName(1, name.length)) - else - NoSymbol + + val sym = + if (jname == fulltpnme.RuntimeNothing) + NothingClass + else if (jname == fulltpnme.RuntimeNull) + NullClass + else + { + val owner = sOwner(jclazz) + val simpleName = scalaSimpleName(jclazz) + + def lookup = { + def coreLookup(name: Name): Symbol = { + val sym = owner.info.decl(name) + sym orElse { + if (name.startsWith(nme.NAME_JOIN_STRING)) + coreLookup(name.subName(1, name.length)) + else + NoSymbol + } + } + + if (nme.isModuleName(simpleName)) { + val moduleName = nme.stripModuleSuffix(simpleName).toTermName + val sym = coreLookup(moduleName) + if (sym == NoSymbol) sym else sym.moduleClass + } else { + coreLookup(simpleName) } } - if (nme.isModuleName(simpleName)) { - val moduleName = nme.stripModuleSuffix(simpleName).toTermName - val sym = coreLookup(moduleName) - if (sym == NoSymbol) sym else sym.moduleClass - } else { - coreLookup(simpleName) + val sym = { + if (jclazz.isMemberClass && !nme.isImplClassName(jname)) { + lookup + } else if (jclazz.isLocalClass || invalidClassName(jname)) { + // local classes and implementation classes not preserved by unpickling - treat as Java + jclassAsScala(jclazz) + } else if (jclazz.isArray) { + ArrayClass + } else javaTypeToValueClass(jclazz) orElse { + // jclazz is top-level - get signature + lookup + // val (clazz, module) = createClassModule( + // sOwner(jclazz), newTypeName(jclazz.getSimpleName), new TopClassCompleter(_, _)) + // classCache enter (jclazz, clazz) + // clazz + } } - } - if (jclazz.isMemberClass && !nme.isImplClassName(jname)) { - lookup - } else if (jclazz.isLocalClass || invalidClassName(jname)) { - // local classes and implementation classes not preserved by unpickling - treat as Java - jclassAsScala(jclazz) - } else if (jclazz.isArray) { - ArrayClass - } else javaTypeToValueClass(jclazz) orElse { - // jclazz is top-level - get signature - lookup - // val (clazz, module) = createClassModule( - // sOwner(jclazz), newTypeName(jclazz.getSimpleName), new TopClassCompleter(_, _)) - // classCache enter (jclazz, clazz) - // clazz - } - } + if (!sym.isType) { + val classloader = jclazz.getClassLoader + println("classloader is: %s of type %s".format(classloader, classloader.getClass)) + def inferClasspath(cl: ClassLoader) = cl match { + case cl: java.net.URLClassLoader => "[" + (cl.getURLs mkString ",") + "]" + case _ => "<unknown>" + } + println("classpath is: %s".format(inferClasspath(classloader))) + def msgNoSym = "no symbol could be loaded from %s (scala equivalent is %s) by name %s".format(owner, jclazz, simpleName) + def msgIsNotType = "not a type: symbol %s loaded from %s (scala equivalent is %s) by name %s".format(sym, owner, jclazz, simpleName) + assert(false, if (sym == NoSymbol) msgNoSym else msgIsNotType) + } - if (!sym.isType) { - def msgNoSym = "no symbol could be loaded from %s (scala equivalent is %s) by name %s".format(owner, jclazz, simpleName) - def msgIsNotType = "not a type: symbol %s loaded from %s (scala equivalent is %s) by name %s".format(sym, owner, jclazz, simpleName) - assert(false, if (sym == NoSymbol) msgNoSym else msgIsNotType) - } + sym + } sym.asInstanceOf[ClassSymbol] } |