diff --git a/apex/Android.bp b/apex/Android.bp
index e234181..14c8771 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -32,6 +32,7 @@
         "apex_test.go",
         "bootclasspath_fragment_test.go",
         "platform_bootclasspath_test.go",
+        "systemserver_classpath_fragment_test.go",
         "vndk_test.go",
     ],
     pluginFor: ["soong_build"],
diff --git a/apex/apex.go b/apex/apex.go
index 208b7bb..31dfa0d 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -102,6 +102,9 @@
 	// List of bootclasspath fragments that are embedded inside this APEX bundle.
 	Bootclasspath_fragments []string
 
+	// List of systemserverclasspath fragments that are embedded inside this APEX bundle.
+	Systemserverclasspath_fragments []string
+
 	// List of java libraries that are embedded inside this APEX bundle.
 	Java_libs []string
 
@@ -570,6 +573,7 @@
 	executableTag   = dependencyTag{name: "executable", payload: true}
 	fsTag           = dependencyTag{name: "filesystem", payload: true}
 	bcpfTag         = dependencyTag{name: "bootclasspathFragment", payload: true, sourceOnly: true}
+	sscpfTag        = dependencyTag{name: "systemserverclasspathFragment", payload: true, sourceOnly: true}
 	compatConfigTag = dependencyTag{name: "compatConfig", payload: true, sourceOnly: true}
 	javaLibTag      = dependencyTag{name: "javaLib", payload: true}
 	jniLibTag       = dependencyTag{name: "jniLib", payload: true}
@@ -744,6 +748,7 @@
 	// Common-arch dependencies come next
 	commonVariation := ctx.Config().AndroidCommonTarget.Variations()
 	ctx.AddFarVariationDependencies(commonVariation, bcpfTag, a.properties.Bootclasspath_fragments...)
+	ctx.AddFarVariationDependencies(commonVariation, sscpfTag, a.properties.Systemserverclasspath_fragments...)
 	ctx.AddFarVariationDependencies(commonVariation, javaLibTag, a.properties.Java_libs...)
 	ctx.AddFarVariationDependencies(commonVariation, bpfTag, a.properties.Bpfs...)
 	ctx.AddFarVariationDependencies(commonVariation, fsTag, a.properties.Filesystems...)
@@ -1668,6 +1673,15 @@
 					filesInfo = append(filesInfo, filesToAdd...)
 					return true
 				}
+			case sscpfTag:
+				{
+					if _, ok := child.(*java.SystemServerClasspathModule); !ok {
+						ctx.PropertyErrorf("systemserverclasspath_fragments", "%q is not a systemserverclasspath_fragment module", depName)
+						return false
+					}
+					filesInfo = append(filesInfo, apexClasspathFragmentProtoFile(ctx, child))
+					return true
+				}
 			case javaLibTag:
 				switch child.(type) {
 				case *java.Library, *java.SdkLibrary, *java.DexImport, *java.SdkLibraryImport, *java.Import:
@@ -1888,7 +1902,16 @@
 					default:
 						ctx.PropertyErrorf("bootclasspath_fragments", "bootclasspath_fragment content %q of type %q is not supported", depName, ctx.OtherModuleType(child))
 					}
-
+				} else if java.IsSystemServerClasspathFragmentContentDepTag(depTag) {
+					// Add the contents of the systemserverclasspath fragment to the apex.
+					switch child.(type) {
+					case *java.Library, *java.SdkLibrary:
+						af := apexFileForJavaModule(ctx, child.(javaModule))
+						filesInfo = append(filesInfo, af)
+						return true // track transitive dependencies
+					default:
+						ctx.PropertyErrorf("systemserverclasspath_fragments", "systemserverclasspath_fragment content %q of type %q is not supported", depName, ctx.OtherModuleType(child))
+					}
 				} else if _, ok := depTag.(android.CopyDirectlyInAnyApexTag); ok {
 					// nothing
 				} else if am.CanHaveApexVariants() && am.IsInstallableToApex() {
@@ -1927,7 +1950,9 @@
 
 	// Sort to have consistent build rules
 	sort.Slice(filesInfo, func(i, j int) bool {
-		return filesInfo[i].builtFile.String() < filesInfo[j].builtFile.String()
+		// Sort by destination path so as to ensure consistent ordering even if the source of the files
+		// changes.
+		return filesInfo[i].path() < filesInfo[j].path()
 	})
 
 	////////////////////////////////////////////////////////////////////////////////////////////
@@ -2051,13 +2076,19 @@
 	}
 
 	// Add classpaths.proto config.
-	classpathProtoOutput := bootclasspathFragmentInfo.ClasspathFragmentProtoOutput
-	classpathProto := newApexFile(ctx, classpathProtoOutput, classpathProtoOutput.Base(), bootclasspathFragmentInfo.ClasspathFragmentProtoInstallDir.Rel(), etc, nil)
-	filesToAdd = append(filesToAdd, classpathProto)
+	filesToAdd = append(filesToAdd, apexClasspathFragmentProtoFile(ctx, module))
 
 	return filesToAdd
 }
 
+// apexClasspathFragmentProtoFile returns apexFile structure defining the classpath.proto config that
+// the module contributes to the apex.
+func apexClasspathFragmentProtoFile(ctx android.ModuleContext, module blueprint.Module) apexFile {
+	fragmentInfo := ctx.OtherModuleProvider(module, java.ClasspathFragmentProtoContentInfoProvider).(java.ClasspathFragmentProtoContentInfo)
+	classpathProtoOutput := fragmentInfo.ClasspathFragmentProtoOutput
+	return newApexFile(ctx, classpathProtoOutput, classpathProtoOutput.Base(), fragmentInfo.ClasspathFragmentProtoInstallDir.Rel(), etc, nil)
+}
+
 // apexFileForBootclasspathFragmentContentModule creates an apexFile for a bootclasspath_fragment
 // content module, i.e. a library that is part of the bootclasspath.
 func apexFileForBootclasspathFragmentContentModule(ctx android.ModuleContext, fragmentModule blueprint.Module, javaModule javaModule) apexFile {
diff --git a/apex/platform_bootclasspath_test.go b/apex/platform_bootclasspath_test.go
index 52b1689..ce12f46 100644
--- a/apex/platform_bootclasspath_test.go
+++ b/apex/platform_bootclasspath_test.go
@@ -20,6 +20,7 @@
 	"android/soong/android"
 	"android/soong/java"
 	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
 )
 
 // Contains tests for platform_bootclasspath logic from java/platform_bootclasspath.go that requires
@@ -174,6 +175,141 @@
 	})
 }
 
+// TestPlatformBootclasspath_AlwaysUsePrebuiltSdks verifies that the build does not fail when
+// AlwaysUsePrebuiltSdk() returns true. The structure of the modules in this test matches what
+// currently exists in some places in the Android build but it is not the intended structure. It is
+// in fact an invalid structure that should cause build failures. However, fixing that structure
+// will take too long so in the meantime this tests the workarounds to avoid build breakages.
+//
+// The main issues with this structure are:
+// 1. There is no prebuilt_bootclasspath_fragment referencing the "foo" java_sdk_library_import.
+// 2. There is no prebuilt_apex/apex_set which makes the dex implementation jar available to the
+//    prebuilt_bootclasspath_fragment and the "foo" java_sdk_library_import.
+//
+// Together these cause the following symptoms:
+// 1. The "foo" java_sdk_library_import does not have a dex implementation jar.
+// 2. The "foo" java_sdk_library_import does not have a myapex variant.
+//
+// TODO(b/179354495): Fix the structure in this test once the main Android build has been fixed.
+func TestPlatformBootclasspath_AlwaysUsePrebuiltSdks(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForTestWithPlatformBootclasspath,
+		prepareForTestWithMyapex,
+		// Configure two libraries, the first is a java_sdk_library whose prebuilt will be used because
+		// of AlwaysUsePrebuiltsSdk() but does not have an appropriate apex variant and does not provide
+		// a boot dex jar. The second is a normal library that is unaffected. The order matters because
+		// if the dependency on myapex:foo is filtered out because of either of those conditions then
+		// the dependencies resolved by the platform_bootclasspath will not match the configured list
+		// and so will fail the test.
+		java.FixtureConfigureUpdatableBootJars("myapex:foo", "myapex:bar"),
+		java.PrepareForTestWithJavaSdkLibraryFiles,
+		android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+			variables.Always_use_prebuilt_sdks = proptools.BoolPtr(true)
+		}),
+		java.FixtureWithPrebuiltApis(map[string][]string{
+			"current": {},
+			"30":      {"foo"},
+		}),
+	).RunTestWithBp(t, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			bootclasspath_fragments: [
+				"mybootclasspath-fragment",
+			],
+			updatable: false,
+		}
+
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+
+		java_library {
+			name: "bar",
+			srcs: ["b.java"],
+			installable: true,
+			apex_available: ["myapex"],
+			permitted_packages: ["bar"],
+		}
+
+		java_sdk_library {
+			name: "foo",
+			srcs: ["b.java"],
+			shared_library: false,
+			public: {
+				enabled: true,
+			},
+			apex_available: ["myapex"],
+			permitted_packages: ["foo"],
+		}
+
+		// A prebuilt java_sdk_library_import that is not preferred by default but will be preferred
+		// because AlwaysUsePrebuiltSdks() is true.
+		java_sdk_library_import {
+			name: "foo",
+			prefer: false,
+			shared_library: false,
+			public: {
+				jars: ["sdk_library/public/foo-stubs.jar"],
+				stub_srcs: ["sdk_library/public/foo_stub_sources"],
+				current_api: "sdk_library/public/foo.txt",
+				removed_api: "sdk_library/public/foo-removed.txt",
+				sdk_version: "current",
+			},
+			apex_available: ["myapex"],
+		}
+
+		// This always depends on the source foo module, its dependencies are not affected by the
+		// AlwaysUsePrebuiltSdks().
+		bootclasspath_fragment {
+			name: "mybootclasspath-fragment",
+			apex_available: [
+				"myapex",
+			],
+			contents: [
+				"foo", "bar",
+			],
+		}
+
+		platform_bootclasspath {
+			name: "myplatform-bootclasspath",
+		}
+`,
+	)
+
+	java.CheckPlatformBootclasspathModules(t, result, "myplatform-bootclasspath", []string{
+		// The configured contents of BootJars.
+		"platform:prebuilt_foo", // Note: This is the platform not myapex variant.
+		"myapex:bar",
+	})
+
+	// Make sure that the myplatform-bootclasspath has the correct dependencies.
+	CheckModuleDependencies(t, result.TestContext, "myplatform-bootclasspath", "android_common", []string{
+		// The following are stubs.
+		"platform:prebuilt_sdk_public_current_android",
+		"platform:prebuilt_sdk_system_current_android",
+		"platform:prebuilt_sdk_test_current_android",
+
+		// Not a prebuilt as no prebuilt existed when it was added.
+		"platform:legacy.core.platform.api.stubs",
+
+		// Needed for generating the boot image.
+		`platform:dex2oatd`,
+
+		// The platform_bootclasspath intentionally adds dependencies on both source and prebuilt
+		// modules when available as it does not know which one will be preferred.
+		//
+		// The source module has an APEX variant but the prebuilt does not.
+		"myapex:foo",
+		"platform:prebuilt_foo",
+
+		// Only a source module exists.
+		"myapex:bar",
+	})
+}
+
 // CheckModuleDependencies checks the dependencies of the selected module against the expected list.
 //
 // The expected list must be a list of strings of the form "<apex>:<module>", where <apex> is the
diff --git a/apex/systemserver_classpath_fragment_test.go b/apex/systemserver_classpath_fragment_test.go
new file mode 100644
index 0000000..e1a101a
--- /dev/null
+++ b/apex/systemserver_classpath_fragment_test.go
@@ -0,0 +1,78 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// 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 apex
+
+import (
+	"testing"
+
+	"android/soong/android"
+	"android/soong/java"
+)
+
+var prepareForTestWithSystemserverclasspathFragment = android.GroupFixturePreparers(
+	java.PrepareForTestWithDexpreopt,
+	PrepareForTestWithApexBuildComponents,
+)
+
+func TestSystemserverclasspathFragmentContents(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForTestWithSystemserverclasspathFragment,
+		prepareForTestWithMyapex,
+	).RunTestWithBp(t, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			systemserverclasspath_fragments: [
+				"mysystemserverclasspathfragment",
+			],
+			updatable: false,
+		}
+
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+
+		java_library {
+			name: "foo",
+			srcs: ["b.java"],
+			installable: true,
+			apex_available: [
+				"myapex",
+			],
+		}
+
+		systemserverclasspath_fragment {
+			name: "mysystemserverclasspathfragment",
+			contents: [
+				"foo",
+			],
+			apex_available: [
+				"myapex",
+			],
+		}
+	`)
+
+	ensureExactContents(t, result.TestContext, "myapex", "android_common_myapex_image", []string{
+		"etc/classpaths/mysystemserverclasspathfragment.pb",
+		"javalib/foo.jar",
+	})
+
+	java.CheckModuleDependencies(t, result.TestContext, "myapex", "android_common_myapex_image", []string{
+		`myapex.key`,
+		`mysystemserverclasspathfragment`,
+	})
+}
diff --git a/java/base.go b/java/base.go
index 03652be..c828503 100644
--- a/java/base.go
+++ b/java/base.go
@@ -229,12 +229,6 @@
 	// otherwise provides defaults libraries to add to the bootclasspath.
 	System_modules *string
 
-	// The name of the module as used in build configuration.
-	//
-	// Allows a library to separate its actual name from the name used in
-	// build configuration, e.g.ctx.Config().BootJars().
-	ConfigurationName *string `blueprint:"mutated"`
-
 	// set the name of the output
 	Stem *string
 
@@ -1223,11 +1217,11 @@
 				return
 			}
 
-			// Update hidden API paths.
-			j.hiddenAPIUpdatePaths(ctx, dexOutputFile, j.implementationJarFile)
+			// Initialize the hiddenapi structure.
+			j.initHiddenAPI(ctx, dexOutputFile, j.implementationJarFile, j.dexProperties.Uncompress_dex)
 
 			// Encode hidden API flags in dex file.
-			dexOutputFile = j.hiddenAPIEncodeDex(ctx, dexOutputFile, proptools.Bool(j.dexProperties.Uncompress_dex))
+			dexOutputFile = j.hiddenAPIEncodeDex(ctx, dexOutputFile)
 
 			// merge dex jar with resources if necessary
 			if j.resourceJar != nil {
@@ -1501,15 +1495,6 @@
 	return proptools.StringDefault(j.deviceProperties.Stem, j.Name())
 }
 
-// ConfigurationName returns the name of the module as used in build configuration.
-//
-// This is usually the same as BaseModuleName() except for the <x>.impl libraries created by
-// java_sdk_library in which case this is the BaseModuleName() without the ".impl" suffix,
-// i.e. just <x>.
-func (j *Module) ConfigurationName() string {
-	return proptools.StringDefault(j.deviceProperties.ConfigurationName, j.BaseModuleName())
-}
-
 func (j *Module) JacocoReportClassesFile() android.Path {
 	return j.jacocoReportClassesFile
 }
diff --git a/java/bootclasspath.go b/java/bootclasspath.go
index 02833ab..634959a 100644
--- a/java/bootclasspath.go
+++ b/java/bootclasspath.go
@@ -29,7 +29,7 @@
 
 func registerBootclasspathBuildComponents(ctx android.RegistrationContext) {
 	ctx.FinalDepsMutators(func(ctx android.RegisterMutatorsContext) {
-		ctx.BottomUp("bootclasspath_deps", bootclasspathDepsMutator)
+		ctx.BottomUp("bootclasspath_deps", bootclasspathDepsMutator).Parallel()
 	})
 }
 
@@ -95,6 +95,15 @@
 	if ctx.OtherModuleDependencyVariantExists(variations, prebuiltName) {
 		ctx.AddVariationDependencies(variations, tag, prebuiltName)
 		addedDep = true
+	} else if ctx.Config().AlwaysUsePrebuiltSdks() && len(variations) > 0 {
+		// TODO(b/179354495): Remove this code path once the Android build has been fully migrated to
+		//  use bootclasspath_fragment properly.
+		// Some prebuilt java_sdk_library modules do not yet have an APEX variations so try and add a
+		// dependency on the non-APEX variant.
+		if ctx.OtherModuleDependencyVariantExists(nil, prebuiltName) {
+			ctx.AddVariationDependencies(nil, tag, prebuiltName)
+			addedDep = true
+		}
 	}
 
 	// If no appropriate variant existing for this, so no dependency could be added, then it is an
diff --git a/java/bootclasspath_fragment.go b/java/bootclasspath_fragment.go
index 16aa5e2..5d8a8e5 100644
--- a/java/bootclasspath_fragment.go
+++ b/java/bootclasspath_fragment.go
@@ -112,6 +112,11 @@
 	Coverage BootclasspathFragmentCoverageAffectedProperties
 
 	Hidden_api HiddenAPIFlagFileProperties
+
+	// Properties that allow a fragment to depend on other fragments. This is needed for hidden API
+	// processing as it needs access to all the classes used by a fragment including those provided
+	// by other fragments.
+	BootclasspathFragmentsDepsProperties
 }
 
 type BootclasspathFragmentModule struct {
@@ -263,22 +268,6 @@
 // BootclasspathFragmentApexContentInfo contains the bootclasspath_fragments contributions to the
 // apex contents.
 type BootclasspathFragmentApexContentInfo struct {
-	// ClasspathFragmentProtoOutput is an output path for the generated classpaths.proto config of this module.
-	//
-	// The file should be copied to a relevant place on device, see ClasspathFragmentProtoInstallDir
-	// for more details.
-	ClasspathFragmentProtoOutput android.OutputPath
-
-	// ClasspathFragmentProtoInstallDir contains information about on device location for the generated classpaths.proto file.
-	//
-	// The path encodes expected sub-location within partitions, i.e. etc/classpaths/<proto-file>,
-	// for ClasspathFragmentProtoOutput. To get sub-location, instead of the full output / make path
-	// use android.InstallPath#Rel().
-	//
-	// This is only relevant for APEX modules as they perform their own installation; while regular
-	// system files are installed via ClasspathFragmentBase#androidMkEntries().
-	ClasspathFragmentProtoInstallDir android.InstallPath
-
 	// The image config, internal to this module (and the dex_bootjars singleton).
 	//
 	// Will be nil if the BootclasspathFragmentApexContentInfo has not been provided for a specific module. That can occur
@@ -391,25 +380,19 @@
 	// Perform hidden API processing.
 	b.generateHiddenAPIBuildActions(ctx, contents)
 
-	// Construct the boot image info from the config.
-	info := BootclasspathFragmentApexContentInfo{
-		ClasspathFragmentProtoInstallDir: b.classpathFragmentBase().installDirPath,
-		ClasspathFragmentProtoOutput:     b.classpathFragmentBase().outputFilepath,
-		imageConfig:                      nil,
-	}
-
 	if !SkipDexpreoptBootJars(ctx) {
 		// Force the GlobalSoongConfig to be created and cached for use by the dex_bootjars
 		// GenerateSingletonBuildActions method as it cannot create it for itself.
 		dexpreopt.GetGlobalSoongConfig(ctx)
-		info.imageConfig = b.getImageConfig(ctx)
 
 		// Only generate the boot image if the configuration does not skip it.
 		b.generateBootImageBuildActions(ctx, contents)
-	}
 
-	// Make it available for other modules.
-	ctx.SetProvider(BootclasspathFragmentApexContentInfoProvider, info)
+		// Make the boot image info available for other modules
+		ctx.SetProvider(BootclasspathFragmentApexContentInfoProvider, BootclasspathFragmentApexContentInfo{
+			imageConfig: b.getImageConfig(ctx),
+		})
+	}
 }
 
 // generateClasspathProtoBuildActions generates all required build actions for classpath.proto config
@@ -448,12 +431,54 @@
 	return imageConfig
 }
 
+// canPerformHiddenAPIProcessing determines whether hidden API processing should be performed.
+//
+// A temporary workaround to avoid existing bootclasspath_fragments that do not provide the
+// appropriate information needed for hidden API processing breaking the build.
+// TODO(b/179354495): Remove this workaround.
+func (b *BootclasspathFragmentModule) canPerformHiddenAPIProcessing(ctx android.ModuleContext) bool {
+	// Hidden API processing is always enabled in tests.
+	if ctx.Config().TestProductVariables != nil {
+		return true
+	}
+	// A module that has fragments should have access to the information it needs in order to perform
+	// hidden API processing.
+	if len(b.properties.Fragments) != 0 {
+		return true
+	}
+
+	// The art bootclasspath fragment does not depend on any other fragments but already supports
+	// hidden API processing.
+	imageName := proptools.String(b.properties.Image_name)
+	if imageName == "art" {
+		return true
+	}
+
+	// Disable it for everything else.
+	return false
+}
+
 // generateHiddenAPIBuildActions generates all the hidden API related build rules.
 func (b *BootclasspathFragmentModule) generateHiddenAPIBuildActions(ctx android.ModuleContext, contents []android.Module) {
 
+	// A temporary workaround to avoid existing bootclasspath_fragments that do not provide the
+	// appropriate information needed for hidden API processing breaking the build.
+	if !b.canPerformHiddenAPIProcessing(ctx) {
+		// Nothing to do.
+		return
+	}
+
 	// Convert the kind specific lists of modules into kind specific lists of jars.
 	stubJarsByKind := hiddenAPIGatherStubLibDexJarPaths(ctx, contents)
 
+	// Performing hidden API processing without stubs is not supported and it is unlikely to ever be
+	// required as the whole point of adding something to the bootclasspath fragment is to add it to
+	// the bootclasspath in order to be used by something else in the system. Without any stubs it
+	// cannot do that.
+	if len(stubJarsByKind) == 0 {
+		return
+	}
+
 	// Store the information for use by other modules.
 	bootclasspathApiInfo := bootclasspathApiInfo{stubJarsByKind: stubJarsByKind}
 	ctx.SetProvider(bootclasspathApiInfoProvider, bootclasspathApiInfo)
@@ -474,15 +499,6 @@
 // produceHiddenAPIAllFlagsFile produces the hidden API all-flags.csv file (and supporting files)
 // for the fragment.
 func (b *BootclasspathFragmentModule) produceHiddenAPIAllFlagsFile(ctx android.ModuleContext, contents []hiddenAPIModule, 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)
diff --git a/java/classpath_fragment.go b/java/classpath_fragment.go
index 7422fa2..7408090 100644
--- a/java/classpath_fragment.go
+++ b/java/classpath_fragment.go
@@ -18,6 +18,7 @@
 
 import (
 	"fmt"
+	"github.com/google/blueprint"
 	"strings"
 
 	"android/soong/android"
@@ -120,6 +121,12 @@
 		FlagWithOutput("--output=", c.outputFilepath)
 
 	rule.Build("classpath_fragment", "Compiling "+c.outputFilepath.String())
+
+	classpathProtoInfo := ClasspathFragmentProtoContentInfo{
+		ClasspathFragmentProtoInstallDir: c.installDirPath,
+		ClasspathFragmentProtoOutput:     c.outputFilepath,
+	}
+	ctx.SetProvider(ClasspathFragmentProtoContentInfoProvider, classpathProtoInfo)
 }
 
 func writeClasspathsJson(ctx android.ModuleContext, output android.WritablePath, jars []classpathJar) {
@@ -157,3 +164,23 @@
 		},
 	}}
 }
+
+var ClasspathFragmentProtoContentInfoProvider = blueprint.NewProvider(ClasspathFragmentProtoContentInfo{})
+
+type ClasspathFragmentProtoContentInfo struct {
+	// ClasspathFragmentProtoOutput is an output path for the generated classpaths.proto config of this module.
+	//
+	// The file should be copied to a relevant place on device, see ClasspathFragmentProtoInstallDir
+	// for more details.
+	ClasspathFragmentProtoOutput android.OutputPath
+
+	// ClasspathFragmentProtoInstallDir contains information about on device location for the generated classpaths.proto file.
+	//
+	// The path encodes expected sub-location within partitions, i.e. etc/classpaths/<proto-file>,
+	// for ClasspathFragmentProtoOutput. To get sub-location, instead of the full output / make path
+	// use android.InstallPath#Rel().
+	//
+	// This is only relevant for APEX modules as they perform their own installation; while regular
+	// system files are installed via ClasspathFragmentBase#androidMkEntries().
+	ClasspathFragmentProtoInstallDir android.InstallPath
+}
diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index be202c0..c1068da 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -766,7 +766,7 @@
 			if len(pp) > 0 {
 				updatablePackages = append(updatablePackages, pp...)
 			} else {
-				ctx.ModuleErrorf("Missing permitted_packages")
+				ctx.OtherModuleErrorf(module, "Missing permitted_packages")
 			}
 		}
 	}
diff --git a/java/hiddenapi.go b/java/hiddenapi.go
index 829c473..1e83824 100644
--- a/java/hiddenapi.go
+++ b/java/hiddenapi.go
@@ -26,27 +26,10 @@
 }, "outFlag", "stubAPIFlags")
 
 type hiddenAPI struct {
-	// The name of the module as it would be used in the boot jars configuration, e.g. without any
-	// prebuilt_ prefix (if it is a prebuilt) and without any ".impl" suffix if it is a
-	// java_sdk_library implementation library.
-	configurationName string
-
 	// True if the module containing this structure contributes to the hiddenapi information or has
 	// that information encoded within it.
 	active bool
 
-	// Identifies the active module variant which will be used as the source of hiddenapi information.
-	//
-	// A class may be compiled into a number of different module variants each of which will need the
-	// hiddenapi information encoded into it and so will be marked as active. However, only one of
-	// them must be used as a source of information by hiddenapi otherwise it will end up with
-	// duplicate entries. That module will have primary=true.
-	//
-	// Note, that modules <x>-hiddenapi that provide additional annotation information for module <x>
-	// that is on the bootclasspath are marked as primary=true as they are the primary source of that
-	// annotation information.
-	primary bool
-
 	// The path to the dex jar that is in the boot class path. If this is nil then the associated
 	// module is not a boot jar, but could be one of the <x>-hiddenapi modules that provide additional
 	// annotations for the <x> boot dex jar but which do not actually provide a boot dex jar
@@ -60,6 +43,10 @@
 	// the UnsupportedAppUsage annotation that need to be extracted as part of the hidden API
 	// processing.
 	classesJarPaths android.Paths
+
+	// The compressed state of the dex file being encoded. This is used to ensure that the encoded
+	// dex file has the same state.
+	uncompressDexState *bool
 }
 
 func (h *hiddenAPI) bootDexJar() android.Path {
@@ -70,6 +57,10 @@
 	return h.classesJarPaths
 }
 
+func (h *hiddenAPI) uncompressDex() *bool {
+	return h.uncompressDexState
+}
+
 // hiddenAPIModule is the interface a module that embeds the hiddenAPI structure must implement.
 type hiddenAPIModule interface {
 	android.Module
@@ -79,18 +70,39 @@
 type hiddenAPIIntf interface {
 	bootDexJar() android.Path
 	classesJars() android.Paths
+	uncompressDex() *bool
 }
 
 var _ hiddenAPIIntf = (*hiddenAPI)(nil)
 
 // Initialize the hiddenapi structure
-func (h *hiddenAPI) initHiddenAPI(ctx android.BaseModuleContext, configurationName string) {
+//
+// uncompressedDexState should be nil when the module is a prebuilt and so does not require hidden
+// API encoding.
+func (h *hiddenAPI) initHiddenAPI(ctx android.ModuleContext, dexJar, classesJar android.Path, uncompressedDexState *bool) {
+
+	// Save the classes jars even if this is not active as they may be used by modular hidden API
+	// processing.
+	classesJars := android.Paths{classesJar}
+	ctx.VisitDirectDepsWithTag(hiddenApiAnnotationsTag, func(dep android.Module) {
+		javaInfo := ctx.OtherModuleProvider(dep, JavaInfoProvider).(JavaInfo)
+		classesJars = append(classesJars, javaInfo.ImplementationJars...)
+	})
+	h.classesJarPaths = classesJars
+
+	// Save the unencoded dex jar so it can be used when generating the
+	// hiddenAPISingletonPathsStruct.stubFlags file.
+	h.bootDexJarPath = dexJar
+
+	h.uncompressDexState = uncompressedDexState
+
 	// If hiddenapi processing is disabled treat this as inactive.
 	if ctx.Config().IsEnvTrue("UNSAFE_DISABLE_HIDDENAPI_FLAGS") {
 		return
 	}
 
-	h.configurationName = configurationName
+	// The context module must implement hiddenAPIModule.
+	module := ctx.Module().(hiddenAPIModule)
 
 	// If the frameworks/base directories does not exist and no prebuilt hidden API flag files have
 	// been configured then it is not possible to do hidden API encoding.
@@ -102,52 +114,7 @@
 	// on the boot jars list because the runtime only enforces access to the hidden API for the
 	// bootclassloader. If information is gathered for modules not on the list then that will cause
 	// failures in the CtsHiddenApiBlocklist... tests.
-	module := ctx.Module()
 	h.active = isModuleInBootClassPath(ctx, module)
-	if !h.active {
-		// The rest of the properties will be ignored if active is false.
-		return
-	}
-
-	// Determine whether this module is the primary module or not.
-	primary := true
-
-	// A prebuilt module is only primary if it is preferred and conversely a source module is only
-	// primary if it has not been replaced by a prebuilt module.
-	if pi, ok := module.(android.PrebuiltInterface); ok {
-		if p := pi.Prebuilt(); p != nil {
-			primary = p.UsePrebuilt()
-		}
-	} else {
-		// The only module that will pass a different configurationName to its module name to this
-		// method is the implementation library of a java_sdk_library. It has a configuration name of
-		// <x> the same as its parent java_sdk_library but a module name of <x>.impl. It is not the
-		// primary module, the java_sdk_library with the name of <x> is.
-		primary = configurationName == ctx.ModuleName()
-
-		// A source module that has been replaced by a prebuilt can never be the primary module.
-		if module.IsReplacedByPrebuilt() {
-			if ctx.HasProvider(android.ApexInfoProvider) {
-				// The source module is in an APEX but the prebuilt module on which it depends is not in an
-				// APEX and so is not the one that will actually be used for hidden API processing. That
-				// means it is not possible to check to see if it is a suitable replacement so just assume
-				// that it is.
-				primary = false
-			} else {
-				ctx.VisitDirectDepsWithTag(android.PrebuiltDepTag, func(prebuilt android.Module) {
-					if h, ok := prebuilt.(hiddenAPIIntf); ok && h.bootDexJar() != nil {
-						primary = false
-					} else {
-						ctx.ModuleErrorf(
-							"hiddenapi has determined that the source module %q should be ignored as it has been"+
-								" replaced by the prebuilt module %q but unfortunately it does not provide a"+
-								" suitable boot dex jar", ctx.ModuleName(), ctx.OtherModuleName(prebuilt))
-					}
-				})
-			}
-		}
-	}
-	h.primary = primary
 }
 
 func isModuleInBootClassPath(ctx android.BaseModuleContext, module android.Module) bool {
@@ -166,13 +133,19 @@
 //
 // Otherwise, it creates a copy of the supplied dex file into which it has encoded the hiddenapi
 // flags and returns this instead of the supplied dex jar.
-func (h *hiddenAPI) hiddenAPIEncodeDex(ctx android.ModuleContext, dexJar android.OutputPath, uncompressDex bool) android.OutputPath {
+func (h *hiddenAPI) hiddenAPIEncodeDex(ctx android.ModuleContext, dexJar android.OutputPath) android.OutputPath {
 
 	if !h.active {
 		return dexJar
 	}
 
-	hiddenAPIJar := android.PathForModuleOut(ctx, "hiddenapi", h.configurationName+".jar").OutputPath
+	// A nil uncompressDexState prevents the dex file from being encoded.
+	if h.uncompressDexState == nil {
+		ctx.ModuleErrorf("cannot encode dex file %s when uncompressDexState is nil", dexJar)
+	}
+	uncompressDex := *h.uncompressDexState
+
+	hiddenAPIJar := android.PathForModuleOut(ctx, "hiddenapi", dexJar.Base()).OutputPath
 
 	// Create a copy of the dex jar which has been encoded with hiddenapi flags.
 	hiddenAPIEncodeDex(ctx, hiddenAPIJar, dexJar, uncompressDex)
@@ -183,27 +156,6 @@
 	return dexJar
 }
 
-// hiddenAPIUpdatePaths generates ninja rules to extract the information from the classes
-// jar, and outputs it to the appropriate module specific CSV file.
-//
-// It also makes the dex jar available for use when generating the
-// hiddenAPISingletonPathsStruct.stubFlags.
-func (h *hiddenAPI) hiddenAPIUpdatePaths(ctx android.ModuleContext, dexJar, classesJar android.Path) {
-
-	// Save the classes jars even if this is not active as they may be used by modular hidden API
-	// processing.
-	classesJars := android.Paths{classesJar}
-	ctx.VisitDirectDepsWithTag(hiddenApiAnnotationsTag, func(dep android.Module) {
-		javaInfo := ctx.OtherModuleProvider(dep, JavaInfoProvider).(JavaInfo)
-		classesJars = append(classesJars, javaInfo.ImplementationJars...)
-	})
-	h.classesJarPaths = classesJars
-
-	// Save the unencoded dex jar so it can be used when generating the
-	// hiddenAPISingletonPathsStruct.stubFlags file.
-	h.bootDexJarPath = dexJar
-}
-
 // buildRuleToGenerateAnnotationFlags builds a ninja rule to generate the annotation-flags.csv file
 // from the classes jars and stub-flags.csv files.
 //
diff --git a/java/hiddenapi_modular.go b/java/hiddenapi_modular.go
index 2dceb65..f5afe5d 100644
--- a/java/hiddenapi_modular.go
+++ b/java/hiddenapi_modular.go
@@ -15,6 +15,7 @@
 package java
 
 import (
+	"fmt"
 	"strings"
 
 	"android/soong/android"
@@ -560,7 +561,25 @@
 	for _, module := range contents {
 		bootDexJar := module.bootDexJar()
 		if bootDexJar == nil {
-			ctx.ModuleErrorf("module %s does not provide a dex jar", module)
+			if ctx.Config().AlwaysUsePrebuiltSdks() {
+				// TODO(b/179354495): Remove this work around when it is unnecessary.
+				// Prebuilt modules like framework-wifi do not yet provide dex implementation jars. So,
+				// create a fake one that will cause a build error only if it is used.
+				fake := android.PathForModuleOut(ctx, "fake/boot-dex/%s.jar", module.Name())
+
+				// Create an error rule that pretends to create the output file but will actually fail if it
+				// is run.
+				ctx.Build(pctx, android.BuildParams{
+					Rule:   android.ErrorRule,
+					Output: fake,
+					Args: map[string]string{
+						"error": fmt.Sprintf("missing dependencies: boot dex jar for %s", module),
+					},
+				})
+				bootDexJars = append(bootDexJars, fake)
+			} else {
+				ctx.ModuleErrorf("module %s does not provide a dex jar", module)
+			}
 		} else {
 			bootDexJars = append(bootDexJars, bootDexJar)
 		}
diff --git a/java/hiddenapi_singleton_test.go b/java/hiddenapi_singleton_test.go
index e6b45ac..dcd363c 100644
--- a/java/hiddenapi_singleton_test.go
+++ b/java/hiddenapi_singleton_test.go
@@ -274,3 +274,56 @@
 
 	android.AssertStringEquals(t, "hiddenapi encode dex rule flags csv", expectedFlagsCsv, actualFlagsCsv)
 }
+
+func TestHiddenAPIEncoding_JavaSdkLibrary(t *testing.T) {
+
+	result := android.GroupFixturePreparers(
+		hiddenApiFixtureFactory,
+		FixtureConfigureBootJars("platform:foo"),
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+
+		// Make sure that the frameworks/base/Android.bp file exists as otherwise hidden API encoding
+		// is disabled.
+		android.FixtureAddTextFile("frameworks/base/Android.bp", ""),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			shared_library: false,
+			compile_dex: true,
+			public: {enabled: true},
+		}
+	`)
+
+	checkDexEncoded := func(t *testing.T, name, unencodedDexJar, encodedDexJar string) {
+		moduleForTests := result.ModuleForTests(name, "android_common")
+
+		encodeDexRule := moduleForTests.Rule("hiddenAPIEncodeDex")
+		actualUnencodedDexJar := encodeDexRule.Input
+
+		// Make sure that the module has its dex jar encoded.
+		android.AssertStringEquals(t, "encode embedded java_library", unencodedDexJar, actualUnencodedDexJar.String())
+
+		// Make sure that the encoded dex jar is the exported one.
+		exportedDexJar := moduleForTests.Module().(UsesLibraryDependency).DexJarBuildPath()
+		android.AssertPathRelativeToTopEquals(t, "encode embedded java_library", encodedDexJar, exportedDexJar)
+	}
+
+	// The java_library embedded with the java_sdk_library must be dex encoded.
+	t.Run("foo", func(t *testing.T) {
+		expectedUnencodedDexJar := "out/soong/.intermediates/foo/android_common/aligned/foo.jar"
+		expectedEncodedDexJar := "out/soong/.intermediates/foo/android_common/hiddenapi/foo.jar"
+		checkDexEncoded(t, "foo", expectedUnencodedDexJar, expectedEncodedDexJar)
+	})
+
+	// The dex jar of the child implementation java_library of the java_sdk_library is not currently
+	// dex encoded.
+	t.Run("foo.impl", func(t *testing.T) {
+		fooImpl := result.ModuleForTests("foo.impl", "android_common")
+		encodeDexRule := fooImpl.MaybeRule("hiddenAPIEncodeDex")
+		if encodeDexRule.Rule != nil {
+			t.Errorf("foo.impl is not expected to be encoded")
+		}
+	})
+}
diff --git a/java/java.go b/java/java.go
index f85de3d..45eb693 100644
--- a/java/java.go
+++ b/java/java.go
@@ -481,11 +481,6 @@
 }
 
 func (j *Library) GenerateAndroidBuildActions(ctx android.ModuleContext) {
-	// Initialize the hiddenapi structure. Pass in the configuration name rather than the module name
-	// so the hidden api will encode the <x>.impl java_ library created by java_sdk_library just as it
-	// would the <x> library if <x> was configured as a boot jar.
-	j.initHiddenAPI(ctx, j.ConfigurationName())
-
 	j.sdkVersion = j.SdkVersion(ctx)
 	j.minSdkVersion = j.MinSdkVersion(ctx)
 
@@ -1241,9 +1236,6 @@
 	j.sdkVersion = j.SdkVersion(ctx)
 	j.minSdkVersion = j.MinSdkVersion(ctx)
 
-	// Initialize the hiddenapi structure.
-	j.initHiddenAPI(ctx, j.BaseModuleName())
-
 	if !ctx.Provider(android.ApexInfoProvider).(android.ApexInfo).IsForPlatform() {
 		j.hideApexVariantFromMake = true
 	}
@@ -1315,7 +1307,9 @@
 			di := ctx.OtherModuleProvider(deapexerModule, android.DeapexerProvider).(android.DeapexerInfo)
 			if dexOutputPath := di.PrebuiltExportPath(j.BaseModuleName(), ".dexjar"); dexOutputPath != nil {
 				j.dexJarFile = dexOutputPath
-				j.hiddenAPIUpdatePaths(ctx, dexOutputPath, outputFile)
+
+				// Initialize the hiddenapi structure.
+				j.initHiddenAPI(ctx, dexOutputPath, outputFile, nil)
 			} else {
 				// This should never happen as a variant for a prebuilt_apex is only created if the
 				// prebuilt_apex has been configured to export the java library dex file.
@@ -1346,11 +1340,11 @@
 				return
 			}
 
-			// Update hidden API paths.
-			j.hiddenAPIUpdatePaths(ctx, dexOutputFile, outputFile)
+			// Initialize the hiddenapi structure.
+			j.initHiddenAPI(ctx, dexOutputFile, outputFile, j.dexProperties.Uncompress_dex)
 
 			// Encode hidden API flags in dex file.
-			dexOutputFile = j.hiddenAPIEncodeDex(ctx, dexOutputFile, proptools.Bool(j.dexProperties.Uncompress_dex))
+			dexOutputFile = j.hiddenAPIEncodeDex(ctx, dexOutputFile)
 
 			j.dexJarFile = dexOutputFile
 		}
diff --git a/java/platform_bootclasspath.go b/java/platform_bootclasspath.go
index c8fafed..6ebeb6b 100644
--- a/java/platform_bootclasspath.go
+++ b/java/platform_bootclasspath.go
@@ -242,8 +242,15 @@
 		} else {
 			name := ctx.OtherModuleName(m)
 			if apexInfo.IsForPlatform() {
-				// error: this jar is part of the platform
-				ctx.ModuleErrorf("module %q from platform is not allowed in the updatable boot jars list", name)
+				// If AlwaysUsePrebuiltSdks() returns true then it is possible that the updatable list will
+				// include platform variants of a prebuilt module due to workarounds elsewhere. In that case
+				// do not treat this as an error.
+				// TODO(b/179354495): Always treat this as an error when migration to bootclasspath_fragment
+				//  modules is complete.
+				if !ctx.Config().AlwaysUsePrebuiltSdks() {
+					// error: this jar is part of the platform
+					ctx.ModuleErrorf("module %q from platform is not allowed in the updatable boot jars list", name)
+				}
 			} else {
 				// TODO(b/177892522): Treat this as an error.
 				// Cannot do that at the moment because framework-wifi and framework-tethering are in the
diff --git a/java/sdk_library.go b/java/sdk_library.go
index f04f837..99eacf4 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -1235,16 +1235,13 @@
 
 // Creates the implementation java library
 func (module *SdkLibrary) createImplLibrary(mctx android.DefaultableHookContext) {
-	moduleNamePtr := proptools.StringPtr(module.BaseModuleName())
-
 	visibility := childModuleVisibility(module.sdkLibraryProperties.Impl_library_visibility)
 
 	props := struct {
-		Name              *string
-		Visibility        []string
-		Instrument        bool
-		Libs              []string
-		ConfigurationName *string
+		Name       *string
+		Visibility []string
+		Instrument bool
+		Libs       []string
 	}{
 		Name:       proptools.StringPtr(module.implLibraryModuleName()),
 		Visibility: visibility,
@@ -1253,9 +1250,6 @@
 		// Set the impl_only libs. Note that the module's "Libs" get appended as well, via the
 		// addition of &module.properties below.
 		Libs: module.sdkLibraryProperties.Impl_only_libs,
-
-		// Make the created library behave as if it had the same name as this module.
-		ConfigurationName: moduleNamePtr,
 	}
 
 	properties := []interface{}{
@@ -2127,8 +2121,7 @@
 			di := ctx.OtherModuleProvider(deapexerModule, android.DeapexerProvider).(android.DeapexerInfo)
 			if dexOutputPath := di.PrebuiltExportPath(module.BaseModuleName(), ".dexjar"); dexOutputPath != nil {
 				module.dexJarFile = dexOutputPath
-				module.initHiddenAPI(ctx, module.configurationName)
-				module.hiddenAPIUpdatePaths(ctx, dexOutputPath, module.findScopePaths(apiScopePublic).stubsImplPath[0])
+				module.initHiddenAPI(ctx, dexOutputPath, module.findScopePaths(apiScopePublic).stubsImplPath[0], nil)
 			} else {
 				// This should never happen as a variant for a prebuilt_apex is only created if the
 				// prebuilt_apex has been configured to export the java library dex file.
diff --git a/java/systemserver_classpath_fragment.go b/java/systemserver_classpath_fragment.go
index 82cdb89..a505c6d 100644
--- a/java/systemserver_classpath_fragment.go
+++ b/java/systemserver_classpath_fragment.go
@@ -17,6 +17,7 @@
 import (
 	"android/soong/android"
 	"android/soong/dexpreopt"
+	"github.com/google/blueprint"
 )
 
 func init() {
@@ -24,8 +25,8 @@
 }
 
 func registerSystemserverClasspathBuildComponents(ctx android.RegistrationContext) {
-	// TODO(satayev): add systemserver_classpath_fragment module
 	ctx.RegisterModuleType("platform_systemserverclasspath", platformSystemServerClasspathFactory)
+	ctx.RegisterModuleType("systemserverclasspath_fragment", systemServerClasspathFactory)
 }
 
 type platformSystemServerClasspathModule struct {
@@ -41,18 +42,18 @@
 	return m
 }
 
-func (b *platformSystemServerClasspathModule) AndroidMkEntries() (entries []android.AndroidMkEntries) {
-	return b.classpathFragmentBase().androidMkEntries()
+func (p *platformSystemServerClasspathModule) AndroidMkEntries() (entries []android.AndroidMkEntries) {
+	return p.classpathFragmentBase().androidMkEntries()
 }
 
-func (b *platformSystemServerClasspathModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
-	configuredJars := configuredJarListToClasspathJars(ctx, b.ClasspathFragmentToConfiguredJarList(ctx), b.classpathType)
-	b.classpathFragmentBase().generateClasspathProtoBuildActions(ctx, configuredJars)
+func (p *platformSystemServerClasspathModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	configuredJars := configuredJarListToClasspathJars(ctx, p.ClasspathFragmentToConfiguredJarList(ctx), p.classpathType)
+	p.classpathFragmentBase().generateClasspathProtoBuildActions(ctx, configuredJars)
 }
 
 var platformSystemServerClasspathKey = android.NewOnceKey("platform_systemserverclasspath")
 
-func (b *platformSystemServerClasspathModule) ClasspathFragmentToConfiguredJarList(ctx android.ModuleContext) android.ConfiguredJarList {
+func (p *platformSystemServerClasspathModule) ClasspathFragmentToConfiguredJarList(ctx android.ModuleContext) android.ConfiguredJarList {
 	return ctx.Config().Once(platformSystemServerClasspathKey, func() interface{} {
 		global := dexpreopt.GetGlobalConfig(ctx)
 
@@ -65,3 +66,64 @@
 		return jars
 	}).(android.ConfiguredJarList)
 }
+
+type SystemServerClasspathModule struct {
+	android.ModuleBase
+	android.ApexModuleBase
+
+	ClasspathFragmentBase
+
+	properties systemServerClasspathFragmentProperties
+}
+
+func (s *SystemServerClasspathModule) ShouldSupportSdkVersion(ctx android.BaseModuleContext, sdkVersion android.ApiLevel) error {
+	return nil
+}
+
+type systemServerClasspathFragmentProperties struct {
+	// The contents of this systemserverclasspath_fragment, could be either java_library, or java_sdk_library.
+	//
+	// The order of this list matters as it is the order that is used in the SYSTEMSERVERCLASSPATH.
+	Contents []string
+}
+
+func systemServerClasspathFactory() android.Module {
+	m := &SystemServerClasspathModule{}
+	m.AddProperties(&m.properties)
+	android.InitApexModule(m)
+	initClasspathFragment(m, SYSTEMSERVERCLASSPATH)
+	android.InitAndroidArchModule(m, android.DeviceSupported, android.MultilibCommon)
+	return m
+}
+
+func (s *SystemServerClasspathModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	if len(s.properties.Contents) == 0 {
+		ctx.PropertyErrorf("contents", "empty contents are not allowed")
+	}
+
+	s.classpathFragmentBase().generateClasspathProtoBuildActions(ctx, configuredJarListToClasspathJars(ctx, s.ClasspathFragmentToConfiguredJarList(ctx)))
+}
+
+func (s *SystemServerClasspathModule) ClasspathFragmentToConfiguredJarList(ctx android.ModuleContext) android.ConfiguredJarList {
+	// TODO(satayev): populate with actual content
+	return android.EmptyConfiguredJarList()
+}
+
+type systemServerClasspathFragmentContentDependencyTag struct {
+	blueprint.BaseDependencyTag
+}
+
+// The tag used for the dependency between the systemserverclasspath_fragment module and its contents.
+var systemServerClasspathFragmentContentDepTag = systemServerClasspathFragmentContentDependencyTag{}
+
+func IsSystemServerClasspathFragmentContentDepTag(tag blueprint.DependencyTag) bool {
+	return tag == systemServerClasspathFragmentContentDepTag
+}
+
+func (s *SystemServerClasspathModule) ComponentDepsMutator(ctx android.BottomUpMutatorContext) {
+	module := ctx.Module()
+
+	for _, name := range s.properties.Contents {
+		ctx.AddDependency(module, systemServerClasspathFragmentContentDepTag, name)
+	}
+}
diff --git a/java/systemserver_classpath_fragment_test.go b/java/systemserver_classpath_fragment_test.go
index 6126d5e..5272f27 100644
--- a/java/systemserver_classpath_fragment_test.go
+++ b/java/systemserver_classpath_fragment_test.go
@@ -20,13 +20,13 @@
 	"android/soong/android"
 )
 
-var prepareForTestWithSystemserverClasspath = android.GroupFixturePreparers(
+var prepareForTestWithSystemServerClasspath = android.GroupFixturePreparers(
 	PrepareForTestWithJavaDefaultModules,
 )
 
-func TestSystemserverClasspathVariant(t *testing.T) {
+func TestPlatformSystemserverClasspathVariant(t *testing.T) {
 	result := android.GroupFixturePreparers(
-		prepareForTestWithSystemserverClasspath,
+		prepareForTestWithSystemServerClasspath,
 		android.FixtureWithRootAndroidBp(`
 			platform_systemserverclasspath {
 				name: "platform-systemserverclasspath",
@@ -38,9 +38,9 @@
 	android.AssertIntEquals(t, "expect 1 variant", 1, len(variants))
 }
 
-func TestSystemserverClasspath_ClasspathFragmentPaths(t *testing.T) {
+func TestPlatformSystemserverClasspath_ClasspathFragmentPaths(t *testing.T) {
 	result := android.GroupFixturePreparers(
-		prepareForTestWithSystemserverClasspath,
+		prepareForTestWithSystemServerClasspath,
 		android.FixtureWithRootAndroidBp(`
 			platform_systemserverclasspath {
 				name: "platform-systemserverclasspath",
@@ -53,9 +53,9 @@
 	android.AssertPathRelativeToTopEquals(t, "install filepath", "out/soong/target/product/test_device/system/etc/classpaths", p.ClasspathFragmentBase.installDirPath)
 }
 
-func TestSystemserverClasspathModule_AndroidMkEntries(t *testing.T) {
+func TestPlatformSystemserverClasspathModule_AndroidMkEntries(t *testing.T) {
 	preparer := android.GroupFixturePreparers(
-		prepareForTestWithSystemserverClasspath,
+		prepareForTestWithSystemServerClasspath,
 		android.FixtureWithRootAndroidBp(`
 			platform_systemserverclasspath {
 				name: "platform-systemserverclasspath",
@@ -95,3 +95,14 @@
 		}
 	})
 }
+
+func TestSystemserverclasspathFragmentWithoutContents(t *testing.T) {
+	prepareForTestWithSystemServerClasspath.
+		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(
+			`\Qempty contents are not allowed\E`)).
+		RunTestWithBp(t, `
+			systemserverclasspath_fragment {
+				name: "systemserverclasspath-fragment",
+			}
+		`)
+}