--- /dev/null	2019-09-18 10:38:12.000000000 -0400
+++ new/src/jdk.jpackage/share/classes/jdk/jpackage/internal/PathGroup.java	2019-09-18 10:38:09.540327900 -0400
@@ -0,0 +1,181 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package jdk.jpackage.internal;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+
+/**
+ * Group of paths.
+ * Each path in the group is assigned a unique id.
+ */
+final class PathGroup {
+    PathGroup(Map<Object, Path> paths) {
+        entries = Collections.unmodifiableMap(paths);
+    }
+
+    Path getPath(Object id) {
+        return entries.get(id);
+    }
+
+    /**
+     * All configured entries.
+     */
+    Collection<Path> paths() {
+        return entries.values();
+    }
+
+    /**
+     * Root entries.
+     */
+    List<Path> roots() {
+        // Sort by the number of path components in ascending order.
+        List<Path> sorted = paths().stream().sorted(
+                (a, b) -> a.getNameCount() - b.getNameCount()).collect(
+                        Collectors.toList());
+
+        return paths().stream().filter(
+                v -> v == sorted.stream().sequential().filter(
+                        v2 -> v == v2 || v2.endsWith(v)).findFirst().get()).collect(
+                        Collectors.toList());
+    }
+
+    long sizeInBytes() throws IOException {
+        long reply = 0;
+        for (Path dir : roots().stream().filter(f -> Files.isDirectory(f)).collect(
+                Collectors.toList())) {
+            reply += Files.walk(dir).filter(p -> Files.isRegularFile(p)).mapToLong(
+                    f -> f.toFile().length()).sum();
+        }
+        return reply;
+    }
+
+    PathGroup resolveAt(Path root) {
+        return new PathGroup(entries.entrySet().stream().collect(
+                Collectors.toMap(e -> e.getKey(),
+                        e -> root.resolve(e.getValue()))));
+    }
+
+    void copy(PathGroup dst) throws IOException {
+        copy(this, dst, false);
+    }
+
+    void move(PathGroup dst) throws IOException {
+        copy(this, dst, true);
+    }
+
+    static interface Facade<T> {
+        PathGroup pathGroup();
+
+        default Collection<Path> paths() {
+            return pathGroup().paths();
+        }
+
+        default List<Path> roots() {
+            return pathGroup().roots();
+        }
+
+        default long sizeInBytes() throws IOException {
+            return pathGroup().sizeInBytes();
+        }
+
+        T resolveAt(Path root);
+
+        default void copy(Facade<T> dst) throws IOException {
+            pathGroup().copy(dst.pathGroup());
+        }
+
+        default void move(Facade<T> dst) throws IOException {
+            pathGroup().move(dst.pathGroup());
+        }
+    }
+
+    private static void copy(PathGroup src, PathGroup dst, boolean move) throws
+            IOException {
+        copy(move, src.entries.keySet().stream().filter(
+                id -> dst.entries.containsKey(id)).map(id -> Map.entry(
+                src.entries.get(id), dst.entries.get(id))).collect(
+                Collectors.toCollection(ArrayList::new)));
+    }
+
+    private static void copy(boolean move, List<Map.Entry<Path, Path>> entries)
+            throws IOException {
+
+        // Reorder entries. Entries with source entries with the least amount of
+        // descending entries found between source entries should go first.
+        entries.sort((e1, e2) -> e1.getKey().getNameCount() - e2.getKey().getNameCount());
+
+        for (var entry : entries.stream().sequential().filter(e -> {
+            return e == entries.stream().sequential().filter(e2 -> isDuplicate(e2, e)).findFirst().get();
+                }).collect(Collectors.toList())) {
+            Path src = entry.getKey();
+            Path dst = entry.getValue();
+
+            if (src.equals(dst)) {
+                continue;
+            }
+
+            Files.createDirectories(dst.getParent());
+            if (move) {
+                Files.move(src, dst);
+            } else if (src.toFile().isDirectory()) {
+                IOUtils.copyRecursive(src, dst);
+            } else {
+                IOUtils.copyFile(src.toFile(), dst.toFile());
+            }
+        }
+    }
+
+    private static boolean isDuplicate(Map.Entry<Path, Path> a,
+            Map.Entry<Path, Path> b) {
+        if (a == b || a.equals(b)) {
+            return true;
+        }
+
+        if (b.getKey().getNameCount() < a.getKey().getNameCount()) {
+            return isDuplicate(b, a);
+        }
+
+        if (!a.getKey().endsWith(b.getKey())) {
+            return false;
+        }
+
+        Path relativeSrcPath = a.getKey().relativize(b.getKey());
+        Path relativeDstPath = a.getValue().relativize(b.getValue());
+
+        return relativeSrcPath.equals(relativeDstPath);
+    }
+
+    private final Map<Object, Path> entries;
+}