diff --git a/java/android_resources.go b/java/android_resources.go
new file mode 100644
index 0000000..47535d2
--- /dev/null
+++ b/java/android_resources.go
@@ -0,0 +1,127 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package java
+
+import (
+	"path/filepath"
+	"strings"
+
+	"android/soong/android"
+)
+
+func init() {
+	android.RegisterPreSingletonType("overlay", OverlaySingletonFactory)
+}
+
+var androidResourceIgnoreFilenames = []string{
+	".svn",
+	".git",
+	".ds_store",
+	"*.scc",
+	".*",
+	"CVS",
+	"thumbs.db",
+	"picasa.ini",
+	"*~",
+}
+
+func androidResourceGlob(ctx android.ModuleContext, dir android.Path) android.Paths {
+	return ctx.GlobFiles(filepath.Join(dir.String(), "**/*"), androidResourceIgnoreFilenames)
+}
+
+type overlayGlobResult struct {
+	dir   string
+	paths android.DirectorySortedPaths
+
+	// Set to true of the product has selected that values in this overlay should not be moved to
+	// Runtime Resource Overlay (RRO) packages.
+	excludeFromRRO bool
+}
+
+const overlayDataKey = "overlayDataKey"
+
+type globbedResourceDir struct {
+	dir   android.Path
+	files android.Paths
+}
+
+func overlayResourceGlob(ctx android.ModuleContext, dir android.Path) (res []globbedResourceDir,
+	rroDirs android.Paths) {
+
+	overlayData := ctx.Config().Get(overlayDataKey).([]overlayGlobResult)
+
+	// Runtime resource overlays (RRO) may be turned on by the product config for some modules
+	rroEnabled := ctx.Config().EnforceRROForModule(ctx.ModuleName())
+
+	for _, data := range overlayData {
+		files := data.paths.PathsInDirectory(filepath.Join(data.dir, dir.String()))
+		if len(files) > 0 {
+			overlayModuleDir := android.PathForSource(ctx, data.dir, dir.String())
+			// If enforce RRO is enabled for this module and this overlay is not in the
+			// exclusion list, ignore the overlay.  The list of ignored overlays will be
+			// passed to Make to be turned into an RRO package.
+			if rroEnabled && !data.excludeFromRRO {
+				rroDirs = append(rroDirs, overlayModuleDir)
+			} else {
+				res = append(res, globbedResourceDir{
+					dir:   overlayModuleDir,
+					files: files,
+				})
+			}
+		}
+	}
+
+	return res, rroDirs
+}
+
+func OverlaySingletonFactory() android.Singleton {
+	return overlaySingleton{}
+}
+
+type overlaySingleton struct{}
+
+func (overlaySingleton) GenerateBuildActions(ctx android.SingletonContext) {
+	var overlayData []overlayGlobResult
+	overlayDirs := ctx.Config().ResourceOverlays()
+	for i := range overlayDirs {
+		// Iterate backwards through the list of overlay directories so that the later, lower-priority
+		// directories in the list show up earlier in the command line to aapt2.
+		overlay := overlayDirs[len(overlayDirs)-1-i]
+		var result overlayGlobResult
+		result.dir = overlay
+
+		// Mark overlays that will not have Runtime Resource Overlays enforced on them
+		// based on the product config
+		result.excludeFromRRO = ctx.Config().EnforceRROExcludedOverlay(overlay)
+
+		files, err := ctx.GlobWithDeps(filepath.Join(overlay, "**/*"), androidResourceIgnoreFilenames)
+		if err != nil {
+			ctx.Errorf("failed to glob resource dir %q: %s", overlay, err.Error())
+			continue
+		}
+		var paths android.Paths
+		for _, f := range files {
+			if !strings.HasSuffix(f, "/") {
+				paths = append(paths, android.PathForSource(ctx, f))
+			}
+		}
+		result.paths = android.PathsToDirectorySortedPaths(paths)
+		overlayData = append(overlayData, result)
+	}
+
+	ctx.Config().Once(overlayDataKey, func() interface{} {
+		return overlayData
+	})
+}