diff --git a/java/bootclasspath_fragment.go b/java/bootclasspath_fragment.go
index 56401b3..b25dff3 100644
--- a/java/bootclasspath_fragment.go
+++ b/java/bootclasspath_fragment.go
@@ -145,7 +145,7 @@
 	BootclasspathFragmentsDepsProperties
 }
 
-type HiddenApiPackageProperties struct {
+type HiddenAPIPackageProperties struct {
 	Hidden_api struct {
 		// Contains prefixes of a package hierarchy that is provided solely by this
 		// bootclasspath_fragment.
@@ -222,8 +222,8 @@
 }
 
 type SourceOnlyBootclasspathProperties struct {
-	HiddenApiPackageProperties
-	Coverage HiddenApiPackageProperties
+	HiddenAPIPackageProperties
+	Coverage HiddenAPIPackageProperties
 }
 
 type BootclasspathFragmentModule struct {
@@ -293,7 +293,7 @@
 				return
 			}
 
-			err = proptools.AppendProperties(&m.sourceOnlyProperties.HiddenApiPackageProperties, &m.sourceOnlyProperties.Coverage, nil)
+			err = proptools.AppendProperties(&m.sourceOnlyProperties.HiddenAPIPackageProperties, &m.sourceOnlyProperties.Coverage, nil)
 			if err != nil {
 				ctx.PropertyErrorf("coverage", "error trying to append hidden api coverage specific properties: %s", err)
 				return
@@ -827,6 +827,9 @@
 	// Populate with flag file paths from the properties.
 	input.extractFlagFilesFromProperties(ctx, &b.properties.Hidden_api)
 
+	// Populate with package rules from the properties.
+	input.extractPackageRulesFromProperties(&b.sourceOnlyProperties.HiddenAPIPackageProperties)
+
 	// Add the stub dex jars from this module's fragment dependencies.
 	input.DependencyStubDexJarsByScope.addStubDexJarsByModule(dependencyHiddenApiInfo.TransitiveStubDexJarsByScope)
 
@@ -862,9 +865,9 @@
 
 	// If the module specifies split_packages or package_prefixes then use those to generate the
 	// signature patterns.
-	splitPackages := b.sourceOnlyProperties.Hidden_api.Split_packages
-	packagePrefixes := b.sourceOnlyProperties.Hidden_api.Package_prefixes
-	singlePackages := b.sourceOnlyProperties.Hidden_api.Single_packages
+	splitPackages := input.SplitPackages
+	packagePrefixes := input.PackagePrefixes
+	singlePackages := input.SinglePackages
 	if splitPackages != nil || packagePrefixes != nil || singlePackages != nil {
 		output.SignaturePatternsPath = buildRuleSignaturePatternsFile(
 			ctx, output.AllFlagsPath, splitPackages, packagePrefixes, singlePackages)
diff --git a/java/hiddenapi_modular.go b/java/hiddenapi_modular.go
index c90b2ff..8b77f36 100644
--- a/java/hiddenapi_modular.go
+++ b/java/hiddenapi_modular.go
@@ -686,13 +686,50 @@
 	return stubDexJars
 }
 
-// HiddenAPIFlagInput encapsulates information obtained from a module and its dependencies that are
-// needed for hidden API flag generation.
-type HiddenAPIFlagInput struct {
+type HiddenAPIPropertyInfo struct {
 	// FlagFilesByCategory contains the flag files that override the initial flags that are derived
 	// from the stub dex files.
 	FlagFilesByCategory FlagFilesByCategory
 
+	// See HiddenAPIFlagFileProperties.Package_prefixes
+	PackagePrefixes []string
+
+	// See HiddenAPIFlagFileProperties.Single_packages
+	SinglePackages []string
+
+	// See HiddenAPIFlagFileProperties.Split_packages
+	SplitPackages []string
+}
+
+// newHiddenAPIPropertyInfo creates a new initialized HiddenAPIPropertyInfo struct.
+func newHiddenAPIPropertyInfo() HiddenAPIPropertyInfo {
+	return HiddenAPIPropertyInfo{
+		FlagFilesByCategory: FlagFilesByCategory{},
+	}
+}
+
+// extractFlagFilesFromProperties extracts the paths to flag files that are specified in the
+// supplied properties and stores them in this struct.
+func (i *HiddenAPIPropertyInfo) extractFlagFilesFromProperties(ctx android.ModuleContext, p *HiddenAPIFlagFileProperties) {
+	for _, category := range HiddenAPIFlagFileCategories {
+		paths := android.PathsForModuleSrc(ctx, category.propertyValueReader(p))
+		i.FlagFilesByCategory[category] = paths
+	}
+}
+
+// extractPackageRulesFromProperties extracts the package rules that are specified in the supplied
+// properties and stores them in this struct.
+func (i *HiddenAPIPropertyInfo) extractPackageRulesFromProperties(p *HiddenAPIPackageProperties) {
+	i.PackagePrefixes = p.Hidden_api.Package_prefixes
+	i.SinglePackages = p.Hidden_api.Single_packages
+	i.SplitPackages = p.Hidden_api.Split_packages
+}
+
+// HiddenAPIFlagInput encapsulates information obtained from a module and its dependencies that are
+// needed for hidden API flag generation.
+type HiddenAPIFlagInput struct {
+	HiddenAPIPropertyInfo
+
 	// StubDexJarsByScope contains the stub dex jars for different *HiddenAPIScope and which determine
 	// the initial flags for each dex member.
 	StubDexJarsByScope StubDexJarsByModule
@@ -714,10 +751,10 @@
 	RemovedTxtFiles android.Paths
 }
 
-// newHiddenAPIFlagInput creates a new initialize HiddenAPIFlagInput struct.
+// newHiddenAPIFlagInput creates a new initialized HiddenAPIFlagInput struct.
 func newHiddenAPIFlagInput() HiddenAPIFlagInput {
 	input := HiddenAPIFlagInput{
-		FlagFilesByCategory:          FlagFilesByCategory{},
+		HiddenAPIPropertyInfo:        newHiddenAPIPropertyInfo(),
 		StubDexJarsByScope:           StubDexJarsByModule{},
 		DependencyStubDexJarsByScope: StubDexJarsByModule{},
 		AdditionalStubDexJarsByScope: StubDexJarsByModule{},
@@ -773,15 +810,6 @@
 	i.RemovedTxtFiles = android.SortedUniquePaths(i.RemovedTxtFiles)
 }
 
-// extractFlagFilesFromProperties extracts the paths to flag files that are specified in the
-// supplied properties and stores them in this struct.
-func (i *HiddenAPIFlagInput) extractFlagFilesFromProperties(ctx android.ModuleContext, p *HiddenAPIFlagFileProperties) {
-	for _, category := range HiddenAPIFlagFileCategories {
-		paths := android.PathsForModuleSrc(ctx, category.propertyValueReader(p))
-		i.FlagFilesByCategory[category] = paths
-	}
-}
-
 func (i *HiddenAPIFlagInput) transitiveStubDexJarsByScope() StubDexJarsByModule {
 	transitive := i.DependencyStubDexJarsByScope
 	transitive.addStubDexJarsByModule(i.StubDexJarsByScope)