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Diffstat (limited to 'compiler/src/dotty/tools/dotc/classpath/ZipAndJarFileLookupFactory.scala')
-rw-r--r-- | compiler/src/dotty/tools/dotc/classpath/ZipAndJarFileLookupFactory.scala | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/compiler/src/dotty/tools/dotc/classpath/ZipAndJarFileLookupFactory.scala b/compiler/src/dotty/tools/dotc/classpath/ZipAndJarFileLookupFactory.scala new file mode 100644 index 000000000..5210c699e --- /dev/null +++ b/compiler/src/dotty/tools/dotc/classpath/ZipAndJarFileLookupFactory.scala @@ -0,0 +1,176 @@ +/* + * Copyright (c) 2014 Contributor. All rights reserved. + */ +package dotty.tools.dotc.classpath + +import java.io.File +import java.net.URL +import scala.annotation.tailrec +import scala.reflect.io.{AbstractFile, FileZipArchive, ManifestResources} +import dotty.tools.io.ClassPath +import dotty.tools.dotc.config.Settings +import dotty.tools.dotc.core.Contexts.Context +import FileUtils._ + +/** + * A trait providing an optional cache for classpath entries obtained from zip and jar files. + * It's possible to create such a cache assuming that entries in such files won't change (at + * least will be the same each time we'll load classpath during the lifetime of JVM process) + * - unlike class and source files in directories, which can be modified and recompiled. + * It allows us to e.g. reduce significantly memory used by PresentationCompilers in Scala IDE + * when there are a lot of projects having a lot of common dependencies. + */ +sealed trait ZipAndJarFileLookupFactory { + private val cache = collection.mutable.Map.empty[AbstractFile, ClassPath] + + def create(zipFile: AbstractFile)(implicit ctx: Context): ClassPath = { + if (ctx.settings.YdisableFlatCpCaching.value) createForZipFile(zipFile) + else createUsingCache(zipFile) + } + + protected def createForZipFile(zipFile: AbstractFile): ClassPath + + private def createUsingCache(zipFile: AbstractFile)(implicit ctx: Context): ClassPath = cache.synchronized { + def newClassPathInstance = { + if (ctx.settings.verbose.value || ctx.settings.Ylogcp.value) + println(s"$zipFile is not yet in the classpath cache") + createForZipFile(zipFile) + } + cache.getOrElseUpdate(zipFile, newClassPathInstance) + } +} + +/** + * Manages creation of classpath for class files placed in zip and jar files. + * It should be the only way of creating them as it provides caching. + */ +object ZipAndJarClassPathFactory extends ZipAndJarFileLookupFactory { + private case class ZipArchiveClassPath(zipFile: File) + extends ZipArchiveFileLookup[ClassFileEntryImpl] + with NoSourcePaths { + + override def findClassFile(className: String): Option[AbstractFile] = { + val (pkg, simpleClassName) = PackageNameUtils.separatePkgAndClassNames(className) + classes(pkg).find(_.name == simpleClassName).map(_.file) + } + + override private[dotty] def classes(inPackage: String): Seq[ClassFileEntry] = files(inPackage) + + override protected def createFileEntry(file: FileZipArchive#Entry): ClassFileEntryImpl = ClassFileEntryImpl(file) + override protected def isRequiredFileType(file: AbstractFile): Boolean = file.isClass + } + + /** + * This type of classpath is closely related to the support for JSR-223. + * Its usage can be observed e.g. when running: + * jrunscript -classpath scala-compiler.jar;scala-reflect.jar;scala-library.jar -l scala + * with a particularly prepared scala-library.jar. It should have all classes listed in the manifest like e.g. this entry: + * Name: scala/Function2$mcFJD$sp.class + */ + private case class ManifestResourcesClassPath(file: ManifestResources) extends ClassPath with NoSourcePaths { + override def findClassFile(className: String): Option[AbstractFile] = { + val (pkg, simpleClassName) = PackageNameUtils.separatePkgAndClassNames(className) + classes(pkg).find(_.name == simpleClassName).map(_.file) + } + + override def asClassPathStrings: Seq[String] = Seq(file.path) + + override def asURLs: Seq[URL] = file.toURLs() + + import ManifestResourcesClassPath.PackageFileInfo + import ManifestResourcesClassPath.PackageInfo + + /** + * A cache mapping package name to abstract file for package directory and subpackages of given package. + * + * ManifestResources can iterate through the collections of entries from e.g. remote jar file. + * We can't just specify the path to the concrete directory etc. so we can't just 'jump' into + * given package, when it's needed. On the other hand we can iterate over entries to get + * AbstractFiles, iterate over entries of these files etc. + * + * Instead of traversing a tree of AbstractFiles once and caching all entries or traversing each time, + * when we need subpackages of a given package or its classes, we traverse once and cache only packages. + * Classes for given package can be then easily loaded when they are needed. + */ + private lazy val cachedPackages: collection.mutable.HashMap[String, PackageFileInfo] = { + val packages = collection.mutable.HashMap[String, PackageFileInfo]() + + def getSubpackages(dir: AbstractFile): List[AbstractFile] = + (for (file <- dir if file.isPackage) yield file)(collection.breakOut) + + @tailrec + def traverse(packagePrefix: String, + filesForPrefix: List[AbstractFile], + subpackagesQueue: collection.mutable.Queue[PackageInfo]): Unit = filesForPrefix match { + case pkgFile :: remainingFiles => + val subpackages = getSubpackages(pkgFile) + val fullPkgName = packagePrefix + pkgFile.name + packages.put(fullPkgName, PackageFileInfo(pkgFile, subpackages)) + val newPackagePrefix = fullPkgName + "." + subpackagesQueue.enqueue(PackageInfo(newPackagePrefix, subpackages)) + traverse(packagePrefix, remainingFiles, subpackagesQueue) + case Nil if subpackagesQueue.nonEmpty => + val PackageInfo(packagePrefix, filesForPrefix) = subpackagesQueue.dequeue() + traverse(packagePrefix, filesForPrefix, subpackagesQueue) + case _ => + } + + val subpackages = getSubpackages(file) + packages.put(ClassPath.RootPackage, PackageFileInfo(file, subpackages)) + traverse(ClassPath.RootPackage, subpackages, collection.mutable.Queue()) + packages + } + + override private[dotty] def packages(inPackage: String): Seq[PackageEntry] = cachedPackages.get(inPackage) match { + case None => Seq.empty + case Some(PackageFileInfo(_, subpackages)) => + val prefix = PackageNameUtils.packagePrefix(inPackage) + subpackages.map(packageFile => PackageEntryImpl(prefix + packageFile.name)) + } + + override private[dotty] def classes(inPackage: String): Seq[ClassFileEntry] = cachedPackages.get(inPackage) match { + case None => Seq.empty + case Some(PackageFileInfo(pkg, _)) => + (for (file <- pkg if file.isClass) yield ClassFileEntryImpl(file))(collection.breakOut) + } + + override private[dotty] def list(inPackage: String): ClassPathEntries = ClassPathEntries(packages(inPackage), classes(inPackage)) + } + + private object ManifestResourcesClassPath { + case class PackageFileInfo(packageFile: AbstractFile, subpackages: Seq[AbstractFile]) + case class PackageInfo(packageName: String, subpackages: List[AbstractFile]) + } + + override protected def createForZipFile(zipFile: AbstractFile): ClassPath = + if (zipFile.file == null) createWithoutUnderlyingFile(zipFile) + else ZipArchiveClassPath(zipFile.file) + + private def createWithoutUnderlyingFile(zipFile: AbstractFile) = zipFile match { + case manifestRes: ManifestResources => + ManifestResourcesClassPath(manifestRes) + case _ => + val errorMsg = s"Abstract files which don't have an underlying file and are not ManifestResources are not supported. There was $zipFile" + throw new IllegalArgumentException(errorMsg) + } +} + +/** + * Manages creation of classpath for source files placed in zip and jar files. + * It should be the only way of creating them as it provides caching. + */ +object ZipAndJarSourcePathFactory extends ZipAndJarFileLookupFactory { + private case class ZipArchiveSourcePath(zipFile: File) + extends ZipArchiveFileLookup[SourceFileEntryImpl] + with NoClassPaths { + + override def asSourcePathString: String = asClassPathString + + override private[dotty] def sources(inPackage: String): Seq[SourceFileEntry] = files(inPackage) + + override protected def createFileEntry(file: FileZipArchive#Entry): SourceFileEntryImpl = SourceFileEntryImpl(file) + override protected def isRequiredFileType(file: AbstractFile): Boolean = file.isScalaOrJavaSource + } + + override protected def createForZipFile(zipFile: AbstractFile): ClassPath = ZipArchiveSourcePath(zipFile.file) +} |