diff --git a/java/bootclasspath_fragment.go b/java/bootclasspath_fragment.go
index d8c5453d5..ec61e7094 100644
--- a/java/bootclasspath_fragment.go
+++ b/java/bootclasspath_fragment.go
@@ -120,6 +120,15 @@ type BootclasspathFragmentModule struct {
 	properties bootclasspathFragmentProperties
 }
 
+// commonBootclasspathFragment defines the methods that are implemented by both source and prebuilt
+// bootclasspath fragment modules.
+type commonBootclasspathFragment interface {
+	// produceHiddenAPIAllFlagsFile produces the all-flags.csv and intermediate files.
+	//
+	// Updates the supplied flagFileInfo with the paths to the generated files set.
+	produceHiddenAPIAllFlagsFile(ctx android.ModuleContext, contents []android.Module, stubJarsByKind map[android.SdkKind]android.Paths, flagFileInfo *hiddenAPIFlagFileInfo)
+}
+
 func bootclasspathFragmentFactory() android.Module {
 	m := &BootclasspathFragmentModule{}
 	m.AddProperties(&m.properties)
@@ -381,7 +390,7 @@ func (b *BootclasspathFragmentModule) GenerateAndroidBuildActions(ctx android.Mo
 	})
 
 	// Perform hidden API processing.
-	b.generateHiddenAPIBuildActions(ctx)
+	b.generateHiddenAPIBuildActions(ctx, contents)
 
 	// Construct the boot image info from the config.
 	info := BootclasspathFragmentApexContentInfo{
@@ -441,12 +450,7 @@ func (b *BootclasspathFragmentModule) getImageConfig(ctx android.EarlyModuleCont
 }
 
 // generateHiddenAPIBuildActions generates all the hidden API related build rules.
-func (b *BootclasspathFragmentModule) generateHiddenAPIBuildActions(ctx android.ModuleContext) {
-	// Resolve the properties to paths.
-	flagFileInfo := b.properties.Hidden_api.hiddenAPIFlagFileInfo(ctx)
-
-	// Store the information for use by platform_bootclasspath.
-	ctx.SetProvider(hiddenAPIFlagFileInfoProvider, flagFileInfo)
+func (b *BootclasspathFragmentModule) generateHiddenAPIBuildActions(ctx android.ModuleContext, contents []android.Module) {
 
 	// Convert the kind specific lists of modules into kind specific lists of jars.
 	stubJarsByKind := hiddenAPIGatherStubLibDexJarPaths(ctx)
@@ -454,6 +458,33 @@ func (b *BootclasspathFragmentModule) generateHiddenAPIBuildActions(ctx android.
 	// Store the information for use by other modules.
 	bootclasspathApiInfo := bootclasspathApiInfo{stubJarsByKind: stubJarsByKind}
 	ctx.SetProvider(bootclasspathApiInfoProvider, bootclasspathApiInfo)
+
+	// Resolve the properties to paths.
+	flagFileInfo := b.properties.Hidden_api.hiddenAPIFlagFileInfo(ctx)
+
+	// Delegate the production of the hidden API all flags file to a module type specific method.
+	common := ctx.Module().(commonBootclasspathFragment)
+	common.produceHiddenAPIAllFlagsFile(ctx, contents, stubJarsByKind, &flagFileInfo)
+
+	// Store the information for use by platform_bootclasspath.
+	ctx.SetProvider(hiddenAPIFlagFileInfoProvider, flagFileInfo)
+}
+
+// produceHiddenAPIAllFlagsFile produces the hidden API all-flags.csv file (and supporting files)
+// for the fragment.
+func (b *BootclasspathFragmentModule) produceHiddenAPIAllFlagsFile(ctx android.ModuleContext, contents []android.Module, stubJarsByKind map[android.SdkKind]android.Paths, flagFileInfo *hiddenAPIFlagFileInfo) {
+	// If no stubs have been provided then don't perform hidden API processing. This is a temporary
+	// workaround to avoid existing bootclasspath_fragments that do not provide stubs breaking the
+	// build.
+	// TODO(b/179354495): Remove this workaround.
+	if len(stubJarsByKind) == 0 {
+		// Nothing to do.
+		return
+	}
+
+	// Generate the rules to create the hidden API flags and update the supplied flagFileInfo with the
+	// paths to the created files.
+	hiddenAPIGenerateAllFlagsForBootclasspathFragment(ctx, contents, stubJarsByKind, flagFileInfo)
 }
 
 // generateBootImageBuildActions generates ninja rules to create the boot image if required for this
@@ -534,6 +565,32 @@ type bootclasspathFragmentSdkMemberProperties struct {
 
 	// Flag files by *hiddenAPIFlagFileCategory
 	Flag_files_by_category map[*hiddenAPIFlagFileCategory]android.Paths
+
+	// The path to the generated stub-flags.csv file.
+	Stub_flags_path android.OptionalPath
+
+	// The path to the generated annotation-flags.csv file.
+	Annotation_flags_path android.OptionalPath
+
+	// The path to the generated metadata.csv file.
+	Metadata_path android.OptionalPath
+
+	// The path to the generated index.csv file.
+	Index_path android.OptionalPath
+
+	// The path to the generated all-flags.csv file.
+	All_flags_path android.OptionalPath
+}
+
+func pathsToOptionalPath(paths android.Paths) android.OptionalPath {
+	switch len(paths) {
+	case 0:
+		return android.OptionalPath{}
+	case 1:
+		return android.OptionalPathForPath(paths[0])
+	default:
+		panic(fmt.Errorf("expected 0 or 1 paths, found %q", paths))
+	}
 }
 
 func (b *bootclasspathFragmentSdkMemberProperties) PopulateFromVariant(ctx android.SdkMemberContext, variant android.Module) {
@@ -547,6 +604,13 @@ func (b *bootclasspathFragmentSdkMemberProperties) PopulateFromVariant(ctx andro
 	flagFileInfo := mctx.OtherModuleProvider(module, hiddenAPIFlagFileInfoProvider).(hiddenAPIFlagFileInfo)
 	b.Flag_files_by_category = flagFileInfo.categoryToPaths
 
+	// Copy all the generated file paths.
+	b.Stub_flags_path = pathsToOptionalPath(flagFileInfo.StubFlagsPaths)
+	b.Annotation_flags_path = pathsToOptionalPath(flagFileInfo.AnnotationFlagsPaths)
+	b.Metadata_path = pathsToOptionalPath(flagFileInfo.MetadataPaths)
+	b.Index_path = pathsToOptionalPath(flagFileInfo.IndexPaths)
+	b.All_flags_path = pathsToOptionalPath(flagFileInfo.AllFlagsPaths)
+
 	// Copy stub_libs properties.
 	b.Stub_libs = module.properties.Api.Stub_libs
 	b.Core_platform_stub_libs = module.properties.Core_platform_api.Stub_libs
@@ -573,14 +637,17 @@ func (b *bootclasspathFragmentSdkMemberProperties) AddToPropertySet(ctx android.
 		corePlatformApiPropertySet.AddPropertyWithTag("stub_libs", b.Core_platform_stub_libs, requiredMemberDependency)
 	}
 
+	hiddenAPISet := propertySet.AddPropertySet("hidden_api")
+	hiddenAPIDir := "hiddenapi"
+
+	// Copy manually curated flag files specified on the bootclasspath_fragment.
 	if b.Flag_files_by_category != nil {
-		hiddenAPISet := propertySet.AddPropertySet("hidden_api")
 		for _, category := range hiddenAPIFlagFileCategories {
 			paths := b.Flag_files_by_category[category]
 			if len(paths) > 0 {
 				dests := []string{}
 				for _, p := range paths {
-					dest := filepath.Join("hiddenapi", p.Base())
+					dest := filepath.Join(hiddenAPIDir, p.Base())
 					builder.CopyToSnapshot(p, dest)
 					dests = append(dests, dest)
 				}
@@ -588,10 +655,47 @@ func (b *bootclasspathFragmentSdkMemberProperties) AddToPropertySet(ctx android.
 			}
 		}
 	}
+
+	copyOptionalPath := func(path android.OptionalPath, property string) {
+		if path.Valid() {
+			p := path.Path()
+			dest := filepath.Join(hiddenAPIDir, p.Base())
+			builder.CopyToSnapshot(p, dest)
+			hiddenAPISet.AddProperty(property, dest)
+		}
+	}
+
+	// Copy all the generated files, if available.
+	copyOptionalPath(b.Stub_flags_path, "stub_flags")
+	copyOptionalPath(b.Annotation_flags_path, "annotation_flags")
+	copyOptionalPath(b.Metadata_path, "metadata")
+	copyOptionalPath(b.Index_path, "index")
+	copyOptionalPath(b.All_flags_path, "all_flags")
 }
 
 var _ android.SdkMemberType = (*bootclasspathFragmentMemberType)(nil)
 
+// prebuiltBootclasspathFragmentProperties contains additional prebuilt_bootclasspath_fragment
+// specific properties.
+type prebuiltBootclasspathFragmentProperties struct {
+	Hidden_api struct {
+		// The path to the stub-flags.csv file created by the bootclasspath_fragment.
+		Stub_flags *string `android:"path"`
+
+		// The path to the annotation-flags.csv file created by the bootclasspath_fragment.
+		Annotation_flags *string `android:"path"`
+
+		// The path to the metadata.csv file created by the bootclasspath_fragment.
+		Metadata *string `android:"path"`
+
+		// The path to the index.csv file created by the bootclasspath_fragment.
+		Index *string `android:"path"`
+
+		// The path to the all-flags.csv file created by the bootclasspath_fragment.
+		All_flags *string `android:"path"`
+	}
+}
+
 // A prebuilt version of the bootclasspath_fragment module.
 //
 // At the moment this is basically just a bootclasspath_fragment module that can be used as a
@@ -600,6 +704,9 @@ var _ android.SdkMemberType = (*bootclasspathFragmentMemberType)(nil)
 type prebuiltBootclasspathFragmentModule struct {
 	BootclasspathFragmentModule
 	prebuilt android.Prebuilt
+
+	// Additional prebuilt specific properties.
+	prebuiltProperties prebuiltBootclasspathFragmentProperties
 }
 
 func (module *prebuiltBootclasspathFragmentModule) Prebuilt() *android.Prebuilt {
@@ -610,9 +717,29 @@ func (module *prebuiltBootclasspathFragmentModule) Name() string {
 	return module.prebuilt.Name(module.ModuleBase.Name())
 }
 
+// produceHiddenAPIAllFlagsFile returns a path to the prebuilt all-flags.csv or nil if none is
+// specified.
+func (module *prebuiltBootclasspathFragmentModule) produceHiddenAPIAllFlagsFile(ctx android.ModuleContext, _ []android.Module, _ map[android.SdkKind]android.Paths, flagFileInfo *hiddenAPIFlagFileInfo) {
+	pathsForOptionalSrc := func(src *string) android.Paths {
+		if src == nil {
+			// TODO(b/179354495): Fail if this is not provided once prebuilts have been updated.
+			return nil
+		}
+		return android.Paths{android.PathForModuleSrc(ctx, *src)}
+	}
+
+	flagFileInfo.StubFlagsPaths = pathsForOptionalSrc(module.prebuiltProperties.Hidden_api.Stub_flags)
+	flagFileInfo.AnnotationFlagsPaths = pathsForOptionalSrc(module.prebuiltProperties.Hidden_api.Annotation_flags)
+	flagFileInfo.MetadataPaths = pathsForOptionalSrc(module.prebuiltProperties.Hidden_api.Metadata)
+	flagFileInfo.IndexPaths = pathsForOptionalSrc(module.prebuiltProperties.Hidden_api.Index)
+	flagFileInfo.AllFlagsPaths = pathsForOptionalSrc(module.prebuiltProperties.Hidden_api.All_flags)
+}
+
+var _ commonBootclasspathFragment = (*prebuiltBootclasspathFragmentModule)(nil)
+
 func prebuiltBootclasspathFragmentFactory() android.Module {
 	m := &prebuiltBootclasspathFragmentModule{}
-	m.AddProperties(&m.properties)
+	m.AddProperties(&m.properties, &m.prebuiltProperties)
 	// This doesn't actually have any prebuilt files of its own so pass a placeholder for the srcs
 	// array.
 	android.InitPrebuiltModule(m, &[]string{"placeholder"})
diff --git a/java/hiddenapi_modular.go b/java/hiddenapi_modular.go
index 335f5b861..817452499 100644
--- a/java/hiddenapi_modular.go
+++ b/java/hiddenapi_modular.go
@@ -166,7 +166,7 @@ var sdkKindToHiddenapiListOption = map[android.SdkKind]string{
 //
 // The rule is initialized but not built so that the caller can modify it and select an appropriate
 // name.
-func ruleToGenerateHiddenAPIStubFlagsFile(ctx android.BuilderContext, outputPath android.OutputPath, bootDexJars android.Paths, sdkKindToPathList map[android.SdkKind]android.Paths) *android.RuleBuilder {
+func ruleToGenerateHiddenAPIStubFlagsFile(ctx android.BuilderContext, outputPath android.WritablePath, bootDexJars android.Paths, sdkKindToPathList map[android.SdkKind]android.Paths) *android.RuleBuilder {
 	// Singleton rule which applies hiddenapi on all boot class path dex files.
 	rule := android.NewRuleBuilder(pctx, ctx)
 
@@ -338,23 +338,49 @@ var hiddenAPIFlagFileCategories = []*hiddenAPIFlagFileCategory{
 	},
 }
 
-// hiddenAPIFlagFileInfo contains paths resolved from HiddenAPIFlagFileProperties
+// hiddenAPIFlagFileInfo contains paths resolved from HiddenAPIFlagFileProperties and also generated
+// by hidden API processing.
+//
+// This is used both for an individual bootclasspath_fragment to provide it to other modules and
+// for a module to collate the files from the fragments it depends upon. That is why the fields are
+// all Paths even though they are initialized with a single path.
 type hiddenAPIFlagFileInfo struct {
 	// categoryToPaths maps from the flag file category to the paths containing information for that
 	// category.
 	categoryToPaths map[*hiddenAPIFlagFileCategory]android.Paths
+
+	// The paths to the generated stub-flags.csv files.
+	StubFlagsPaths android.Paths
+
+	// The paths to the generated annotation-flags.csv files.
+	AnnotationFlagsPaths android.Paths
+
+	// The paths to the generated metadata.csv files.
+	MetadataPaths android.Paths
+
+	// The paths to the generated index.csv files.
+	IndexPaths android.Paths
+
+	// The paths to the generated all-flags.csv files.
+	AllFlagsPaths android.Paths
 }
 
 func (i *hiddenAPIFlagFileInfo) append(other hiddenAPIFlagFileInfo) {
 	for _, category := range hiddenAPIFlagFileCategories {
 		i.categoryToPaths[category] = append(i.categoryToPaths[category], other.categoryToPaths[category]...)
 	}
+	i.StubFlagsPaths = append(i.StubFlagsPaths, other.StubFlagsPaths...)
+	i.AnnotationFlagsPaths = append(i.AnnotationFlagsPaths, other.AnnotationFlagsPaths...)
+	i.MetadataPaths = append(i.MetadataPaths, other.MetadataPaths...)
+	i.IndexPaths = append(i.IndexPaths, other.IndexPaths...)
+	i.AllFlagsPaths = append(i.AllFlagsPaths, other.AllFlagsPaths...)
 }
 
 var hiddenAPIFlagFileInfoProvider = blueprint.NewProvider(hiddenAPIFlagFileInfo{})
 
-// ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
-// flags from all the modules, the stub flags, augmented with some additional configuration files.
+// buildRuleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from
+// the flags from all the modules, the stub flags, augmented with some additional configuration
+// files.
 //
 // baseFlagsPath is the path to the flags file containing all the information from the stubs plus
 // an entry for every single member in the dex implementation jars of the individual modules. Every
@@ -365,19 +391,7 @@ var hiddenAPIFlagFileInfoProvider = blueprint.NewProvider(hiddenAPIFlagFileInfo{
 //
 // augmentationInfo is a struct containing paths to files that augment the information provided by
 // the moduleSpecificFlagsPaths.
-// ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
-// flags from all the modules, the stub flags, augmented with some additional configuration files.
-//
-// baseFlagsPath is the path to the flags file containing all the information from the stubs plus
-// an entry for every single member in the dex implementation jars of the individual modules. Every
-// signature in any of the other files MUST be included in this file.
-//
-// moduleSpecificFlagsPaths are the paths to the flags files generated by each module using
-// information from the baseFlagsPath as well as from annotations within the source.
-//
-// augmentationInfo is a struct containing paths to files that augment the information provided by
-// the moduleSpecificFlagsPaths.
-func ruleToGenerateHiddenApiFlags(ctx android.BuilderContext, outputPath android.WritablePath, baseFlagsPath android.Path, moduleSpecificFlagsPaths android.Paths, augmentationInfo hiddenAPIFlagFileInfo) {
+func buildRuleToGenerateHiddenApiFlags(ctx android.BuilderContext, name, desc string, outputPath android.WritablePath, baseFlagsPath android.Path, moduleSpecificFlagsPaths android.Paths, flagFileInfo *hiddenAPIFlagFileInfo) {
 	tempPath := tempPathForRestat(ctx, outputPath)
 	rule := android.NewRuleBuilder(pctx, ctx)
 	command := rule.Command().
@@ -388,7 +402,7 @@ func ruleToGenerateHiddenApiFlags(ctx android.BuilderContext, outputPath android
 
 	// Add the options for the different categories of flag files.
 	for _, category := range hiddenAPIFlagFileCategories {
-		paths := augmentationInfo.categoryToPaths[category]
+		paths := flagFileInfo.categoryToPaths[category]
 		for _, path := range paths {
 			category.commandMutator(command, path)
 		}
@@ -396,5 +410,103 @@ func ruleToGenerateHiddenApiFlags(ctx android.BuilderContext, outputPath android
 
 	commitChangeForRestat(rule, tempPath, outputPath)
 
-	rule.Build("hiddenAPIFlagsFile", "hiddenapi flags")
+	rule.Build(name, desc)
+}
+
+// hiddenAPIGenerateAllFlagsForBootclasspathFragment will generate all the flags for a fragment
+// of the bootclasspath.
+//
+// It takes:
+// * Map from android.SdkKind to stub dex jar paths defining the API for that sdk kind.
+// * The list of modules that are the contents of the fragment.
+// * The additional manually curated flag files to use.
+//
+// It generates:
+// * stub-flags.csv
+// * annotation-flags.csv
+// * metadata.csv
+// * index.csv
+// * all-flags.csv
+func hiddenAPIGenerateAllFlagsForBootclasspathFragment(ctx android.ModuleContext, contents []android.Module, stubJarsByKind map[android.SdkKind]android.Paths, flagFileInfo *hiddenAPIFlagFileInfo) {
+
+	hiddenApiSubDir := "modular-hiddenapi"
+
+	bootDexJars := android.Paths{}
+	classesJars := android.Paths{}
+	for _, module := range contents {
+		if hiddenAPI, ok := module.(hiddenAPIIntf); ok {
+			classesJars = append(classesJars, hiddenAPI.classesJars()...)
+			bootDexJar := hiddenAPI.bootDexJar()
+			if bootDexJar == nil {
+				ctx.ModuleErrorf("module %s does not provide a dex jar", module)
+			} else {
+				bootDexJars = append(bootDexJars, bootDexJar)
+			}
+		} else {
+			ctx.ModuleErrorf("module %s does not implement hiddenAPIIntf", module)
+		}
+	}
+
+	// Generate the stub-flags.csv.
+	stubFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "stub-flags.csv")
+	rule := ruleToGenerateHiddenAPIStubFlagsFile(ctx, stubFlagsCSV, bootDexJars, stubJarsByKind)
+	rule.Build("modularHiddenAPIStubFlagsFile", "modular hiddenapi stub flags")
+
+	// Generate the set of flags from the annotations in the source code.
+	annotationFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "annotation-flags.csv")
+	ctx.Build(pctx, android.BuildParams{
+		Rule:        hiddenAPIGenerateCSVRule,
+		Description: "modular hiddenapi annotation flags",
+		Inputs:      classesJars,
+		Output:      annotationFlagsCSV,
+		Implicit:    stubFlagsCSV,
+		Args: map[string]string{
+			"outFlag":      "--write-flags-csv",
+			"stubAPIFlags": stubFlagsCSV.String(),
+		},
+	})
+
+	// Generate the metadata from the annotations in the source code.
+	metadataCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "metadata.csv")
+	ctx.Build(pctx, android.BuildParams{
+		Rule:        hiddenAPIGenerateCSVRule,
+		Description: "modular hiddenapi metadata",
+		Inputs:      classesJars,
+		Output:      metadataCSV,
+		Implicit:    stubFlagsCSV,
+		Args: map[string]string{
+			"outFlag":      "--write-metadata-csv",
+			"stubAPIFlags": stubFlagsCSV.String(),
+		},
+	})
+
+	// Generate the index file from the annotations in the source code.
+	indexCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "index.csv")
+	rule = android.NewRuleBuilder(pctx, ctx)
+	rule.Command().
+		BuiltTool("merge_csv").
+		Flag("--zip_input").
+		Flag("--key_field signature").
+		FlagWithOutput("--output=", indexCSV).
+		Inputs(classesJars)
+	rule.Build("modular-hiddenapi-index", "modular hiddenapi index")
+
+	// Removed APIs need to be marked and in order to do that the flagFileInfo needs to specify files
+	// containing dex signatures of all the removed APIs. In the monolithic files that is done by
+	// manually combining all the removed.txt files for each API and then converting them to dex
+	// signatures, see the combined-removed-dex module. That will all be done automatically in future.
+	// For now removed APIs are ignored.
+	// TODO(b/179354495): handle removed apis automatically.
+
+	// Generate the all-flags.csv which are the flags that will, in future, be encoded into the dex
+	// files.
+	outputPath := android.PathForModuleOut(ctx, hiddenApiSubDir, "all-flags.csv")
+	buildRuleToGenerateHiddenApiFlags(ctx, "modularHiddenApiAllFlags", "modular hiddenapi all flags", outputPath, stubFlagsCSV, android.Paths{annotationFlagsCSV}, flagFileInfo)
+
+	// Store the paths in the info for use by other modules and sdk snapshot generation.
+	flagFileInfo.StubFlagsPaths = android.Paths{stubFlagsCSV}
+	flagFileInfo.AnnotationFlagsPaths = android.Paths{annotationFlagsCSV}
+	flagFileInfo.MetadataPaths = android.Paths{metadataCSV}
+	flagFileInfo.IndexPaths = android.Paths{indexCSV}
+	flagFileInfo.AllFlagsPaths = android.Paths{outputPath}
 }
diff --git a/java/platform_bootclasspath.go b/java/platform_bootclasspath.go
index 1feed3ddd..b5fec95fe 100644
--- a/java/platform_bootclasspath.go
+++ b/java/platform_bootclasspath.go
@@ -364,7 +364,7 @@ func (b *platformBootclasspathModule) generateHiddenAPIBuildActions(ctx android.
 
 	outputPath := hiddenAPISingletonPaths(ctx).flags
 	baseFlagsPath := hiddenAPISingletonPaths(ctx).stubFlags
-	ruleToGenerateHiddenApiFlags(ctx, outputPath, baseFlagsPath, moduleSpecificFlagsPaths, flagFileInfo)
+	buildRuleToGenerateHiddenApiFlags(ctx, "hiddenAPIFlagsFile", "hiddenapi flags", outputPath, baseFlagsPath, moduleSpecificFlagsPaths, &flagFileInfo)
 
 	b.generateHiddenAPIStubFlagsRules(ctx, hiddenAPISupportingModules)
 	b.generateHiddenAPIIndexRules(ctx, hiddenAPISupportingModules)
diff --git a/java/platform_bootclasspath_test.go b/java/platform_bootclasspath_test.go
index 98d46143c..cf2eab370 100644
--- a/java/platform_bootclasspath_test.go
+++ b/java/platform_bootclasspath_test.go
@@ -155,6 +155,8 @@ func TestPlatformBootclasspath(t *testing.T) {
 func TestPlatformBootclasspath_Fragments(t *testing.T) {
 	result := android.GroupFixturePreparers(
 		prepareForTestWithPlatformBootclasspath,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
 		android.FixtureWithRootAndroidBp(`
 			platform_bootclasspath {
 				name: "platform-bootclasspath",
@@ -192,6 +194,9 @@ func TestPlatformBootclasspath_Fragments(t *testing.T) {
 			bootclasspath_fragment {
 				name: "bar-fragment",
 				contents: ["bar"],
+				api: {
+					stub_libs: ["foo"],
+				},
 				hidden_api: {
 					unsupported: [
 							"bar-unsupported.txt",
@@ -227,6 +232,15 @@ func TestPlatformBootclasspath_Fragments(t *testing.T) {
 				sdk_version: "none",
 				compile_dex: true,
 			}
+
+			java_sdk_library {
+				name: "foo",
+				srcs: ["a.java"],
+				public: {
+					enabled: true,
+				},
+				compile_dex: true,
+			}
 		`),
 	).RunTest(t)
 
@@ -240,6 +254,12 @@ func TestPlatformBootclasspath_Fragments(t *testing.T) {
 		expected := []string{fmt.Sprintf("%s.txt", filename), fmt.Sprintf("bar-%s.txt", filename)}
 		android.AssertPathsRelativeToTopEquals(t, message, expected, info.categoryToPaths[category])
 	}
+
+	android.AssertPathsRelativeToTopEquals(t, "stub flags", []string{"out/soong/.intermediates/bar-fragment/android_common/modular-hiddenapi/stub-flags.csv"}, info.StubFlagsPaths)
+	android.AssertPathsRelativeToTopEquals(t, "annotation flags", []string{"out/soong/.intermediates/bar-fragment/android_common/modular-hiddenapi/annotation-flags.csv"}, info.AnnotationFlagsPaths)
+	android.AssertPathsRelativeToTopEquals(t, "metadata flags", []string{"out/soong/.intermediates/bar-fragment/android_common/modular-hiddenapi/metadata.csv"}, info.MetadataPaths)
+	android.AssertPathsRelativeToTopEquals(t, "index flags", []string{"out/soong/.intermediates/bar-fragment/android_common/modular-hiddenapi/index.csv"}, info.IndexPaths)
+	android.AssertPathsRelativeToTopEquals(t, "all flags", []string{"out/soong/.intermediates/bar-fragment/android_common/modular-hiddenapi/all-flags.csv"}, info.AllFlagsPaths)
 }
 
 func TestPlatformBootclasspathVariant(t *testing.T) {
diff --git a/sdk/bootclasspath_fragment_sdk_test.go b/sdk/bootclasspath_fragment_sdk_test.go
index 711fe4d62..bd69f06f2 100644
--- a/sdk/bootclasspath_fragment_sdk_test.go
+++ b/sdk/bootclasspath_fragment_sdk_test.go
@@ -246,6 +246,13 @@ prebuilt_bootclasspath_fragment {
     core_platform_api: {
         stub_libs: ["mycoreplatform"],
     },
+    hidden_api: {
+        stub_flags: "hiddenapi/stub-flags.csv",
+        annotation_flags: "hiddenapi/annotation-flags.csv",
+        metadata: "hiddenapi/metadata.csv",
+        index: "hiddenapi/index.csv",
+        all_flags: "hiddenapi/all-flags.csv",
+    },
 }
 
 java_import {
@@ -319,6 +326,13 @@ prebuilt_bootclasspath_fragment {
     core_platform_api: {
         stub_libs: ["mysdk_mycoreplatform@current"],
     },
+    hidden_api: {
+        stub_flags: "hiddenapi/stub-flags.csv",
+        annotation_flags: "hiddenapi/annotation-flags.csv",
+        metadata: "hiddenapi/metadata.csv",
+        index: "hiddenapi/index.csv",
+        all_flags: "hiddenapi/all-flags.csv",
+    },
 }
 
 java_import {
@@ -387,6 +401,11 @@ sdk_snapshot {
 }
 		`),
 		checkAllCopyRules(`
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/stub-flags.csv -> hiddenapi/stub-flags.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/annotation-flags.csv -> hiddenapi/annotation-flags.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/metadata.csv -> hiddenapi/metadata.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/index.csv -> hiddenapi/index.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/all-flags.csv -> hiddenapi/all-flags.csv
 .intermediates/mybootlib/android_common/javac/mybootlib.jar -> java/mybootlib.jar
 .intermediates/myothersdklibrary.stubs/android_common/javac/myothersdklibrary.stubs.jar -> sdk_library/public/myothersdklibrary-stubs.jar
 .intermediates/myothersdklibrary.stubs.source/android_common/metalava/myothersdklibrary.stubs.source_api.txt -> sdk_library/public/myothersdklibrary.txt
@@ -542,6 +561,11 @@ prebuilt_bootclasspath_fragment {
         max_target_o_low_priority: ["hiddenapi/my-max-target-o-low-priority.txt"],
         blocked: ["hiddenapi/my-blocked.txt"],
         unsupported_packages: ["hiddenapi/my-unsupported-packages.txt"],
+        stub_flags: "hiddenapi/stub-flags.csv",
+        annotation_flags: "hiddenapi/annotation-flags.csv",
+        metadata: "hiddenapi/metadata.csv",
+        index: "hiddenapi/index.csv",
+        all_flags: "hiddenapi/all-flags.csv",
     },
 }
 
@@ -578,6 +602,11 @@ my-max-target-p.txt -> hiddenapi/my-max-target-p.txt
 my-max-target-o-low-priority.txt -> hiddenapi/my-max-target-o-low-priority.txt
 my-blocked.txt -> hiddenapi/my-blocked.txt
 my-unsupported-packages.txt -> hiddenapi/my-unsupported-packages.txt
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/stub-flags.csv -> hiddenapi/stub-flags.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/annotation-flags.csv -> hiddenapi/annotation-flags.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/metadata.csv -> hiddenapi/metadata.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/index.csv -> hiddenapi/index.csv
+.intermediates/mybootclasspathfragment/android_common/modular-hiddenapi/all-flags.csv -> hiddenapi/all-flags.csv
 .intermediates/mybootlib/android_common/javac/mybootlib.jar -> java/mybootlib.jar
 .intermediates/mysdklibrary.stubs/android_common/javac/mysdklibrary.stubs.jar -> sdk_library/public/mysdklibrary-stubs.jar
 .intermediates/mysdklibrary.stubs.source/android_common/metalava/mysdklibrary.stubs.source_api.txt -> sdk_library/public/mysdklibrary.txt