WIP better data structures/algorithms for classpath merging

Author: retronym

src/compiler/scala/tools/nsc/classpath/AggregateClassPath.scala

@@ -79,18 +79,26 @@ case class AggregateClassPath(aggregates: Seq[ClassPath]) extends ClassPath {
 
   override private[nsc] def hasPackage(pkg: PackageName) = aggregates.exists(_.hasPackage(pkg))
   override private[nsc] def list(inPackage: PackageName): ClassPathEntries = {
-
-    val (packages, classesAndSources) = aggregates.map { cp =>
+    var packages: java.util.HashSet[PackageEntry] = null
+    val classesAndSources = collection.mutable.ArrayBuffer[ClassRepresentation]()
+    aggregates.foreach { cp =>
       try {
-        cp.list(inPackage)
+        val entries = cp.list(inPackage)
+        if (entries._1.nonEmpty) {
+          if (packages == null) packages = new java.util.HashSet[PackageEntry]()
+          entries._1.foreach(entry => packages.add(entry))
+
+          classesAndSources ++= entries._2
+        }
       } catch {
         case ex: java.io.IOException =>
           val e = FatalError(ex.getMessage)
           e.initCause(ex)
           throw e
       }
-    }.unzip
-    val distinctPackages = packages.flatten.distinct
+    }
+
+    val distinctPackages: Seq[PackageEntry] = if (packages == null) Nil else packages.toArray(new Array[PackageEntry](packages.size()))
     val distinctClassesAndSources = mergeClassesAndSources(classesAndSources)
     ClassPathEntries(distinctPackages, distinctClassesAndSources)
   }
@@ -100,14 +108,13 @@ case class AggregateClassPath(aggregates: Seq[ClassPath]) extends ClassPath {
    * creates an entry containing both of them. If there would be more than one class or source
    * entries for the same class it always would use the first entry of each type found on a classpath.
    */
-  private def mergeClassesAndSources(entries: Seq[Seq[ClassRepresentation]]): Seq[ClassRepresentation] = {
+  private def mergeClassesAndSources(entries: Seq[ClassRepresentation]): Seq[ClassRepresentation] = {
     var count = 0
     val indices = collection.mutable.HashMap[String, Int]()
     val mergedEntries = new ArrayBuffer[ClassRepresentation](1024)
 
     for {
-      partOfEntries <- entries
-      entry <- partOfEntries
+      entry <- entries
     } {
       val name = entry.name
       if (indices contains name) {

src/compiler/scala/tools/nsc/classpath/ZipArchiveFileLookup.scala

@@ -74,7 +74,7 @@ trait ZipArchiveFileLookup[FileEntryType <: ClassRepresentation] extends ClassPa
   }
 
   private def findDirEntry(pkg: PackageName): Option[archive.DirEntry] = {
-    archive.allDirs.get(pkg.dirPathTrailingSlash)
+    Option(archive.allDirs.get(pkg.dirPathTrailingSlash))
   }
 
 

src/library/scala/collection/mutable/AnyRefMap.scala

@@ -108,8 +108,10 @@ extends AbstractMap[K, V]
     var e = h & mask
     var x = 0
     var g = 0
-    while ({ g = _hashes(e); g != 0}) {
-      if (g == h && { val q = _keys(e); (q eq k) || ((q ne null) && (q equals k)) }) return e
+    val hashes = _hashes
+    val keys = _keys
+    while ({ g = hashes(e); g != 0}) {
+      if (g == h && { val q = keys(e); (q eq k) || ((q ne null) && (q equals k)) }) return e
       x += 1
       e = (e + 2*(x+1)*x - 3) & mask
     }

src/reflect/scala/reflect/io/ZipArchive.scala

@@ -108,19 +108,19 @@ abstract class ZipArchive(override val file: JFile, release: Option[String]) ext
     }
   }
 
-  private def ensureDir(dirs: mutable.Map[String, DirEntry], path: String, zipEntry: ZipEntry): DirEntry = {
+  private def ensureDir(dirs: java.util.Map[String, DirEntry], path: String, zipEntry: ZipEntry): DirEntry = {
     dirs get path match {
-      case Some(v) => v
-      case None =>
+      case null =>
         val parent = ensureDir(dirs, dirName(path), null)
         val dir = new DirEntry(path)
         parent.entries(baseName(path)) = dir
-        dirs(path) = dir
+        dirs.put(path, dir)
         dir
+      case v => v
     }
   }
 
-  protected def getDir(dirs: mutable.Map[String, DirEntry], entry: ZipEntry): DirEntry = {
+  protected def getDir(dirs: java.util.Map[String, DirEntry], entry: ZipEntry): DirEntry = {
     if (entry.isDirectory) ensureDir(dirs, entry.getName, entry)
     else ensureDir(dirs, dirName(entry.getName), null)
   }
@@ -172,10 +172,10 @@ final class FileZipArchive(file: JFile, release: Option[String]) extends ZipArch
     override def sizeOption: Option[Int] = Some(zipEntry.getSize.toInt)
   }
 
-  private[this] val dirs = mutable.HashMap[String, DirEntry]()
+  private[this] val dirs = new java.util.HashMap[String, DirEntry]()
   lazy val root: DirEntry = {
     val root = new DirEntry("/")
-    dirs("/") = root
+    dirs.put("/", root)
     val zipFile = openZipFile()
     val enum    = zipFile.entries()
 
@@ -209,7 +209,7 @@ final class FileZipArchive(file: JFile, release: Option[String]) extends ZipArch
     root
   }
 
-  lazy val allDirs: mutable.HashMap[String, DirEntry] = { root; dirs }
+  lazy val allDirs: java.util.Map[String, DirEntry] = { root; dirs }
 
   def iterator: Iterator[Entry] = root.iterator
 
@@ -234,7 +234,8 @@ final class FileZipArchive(file: JFile, release: Option[String]) extends ZipArch
 final class URLZipArchive(val url: URL) extends ZipArchive(null) {
   def iterator: Iterator[Entry] = {
     val root     = new DirEntry("/")
-    val dirs     = mutable.HashMap[String, DirEntry]("" -> root)
+    val dirs     = new java.util.HashMap[String, DirEntry]()
+    dirs.put("", root)
     val in       = new ZipInputStream(new ByteArrayInputStream(Streamable.bytes(input)))
     closeables ::= in
 
@@ -307,7 +308,8 @@ final class URLZipArchive(val url: URL) extends ZipArchive(null) {
 final class ManifestResources(val url: URL) extends ZipArchive(null) {
   def iterator = {
     val root     = new DirEntry("/")
-    val dirs     = mutable.HashMap[String, DirEntry]("" -> root)
+    val dirs     = new java.util.HashMap[String, DirEntry]
+    dirs.put("", root)
     val manifest = new Manifest(input)
     closeables ::= input