diff --git a/android/api_levels.go b/android/api_levels.go
index 84ab27c..93583bc 100644
--- a/android/api_levels.go
+++ b/android/api_levels.go
@@ -289,6 +289,7 @@
 			"P":     28,
 			"Q":     29,
 			"R":     30,
+			"S":     31,
 		}
 
 		// TODO: Differentiate "current" and "future".
@@ -331,6 +332,7 @@
 			"P":     28,
 			"Q":     29,
 			"R":     30,
+			"S":     31,
 		}
 		for i, codename := range config.PlatformVersionActiveCodenames() {
 			apiLevelsMap[codename] = previewAPILevelBase + i
diff --git a/java/droidstubs.go b/java/droidstubs.go
index 2154ec9..7bfdc55 100644
--- a/java/droidstubs.go
+++ b/java/droidstubs.go
@@ -363,7 +363,8 @@
 	cmd.FlagWithOutput("--generate-api-levels ", d.apiVersionsXml)
 	cmd.FlagWithInput("--apply-api-levels ", d.apiVersionsXml)
 	cmd.FlagWithArg("--current-version ", ctx.Config().PlatformSdkVersion().String())
-	cmd.FlagWithArg("--current-codename ", ctx.Config().PlatformSdkCodename())
+	// STOPSHIP: RESTORE THIS LOGIC WHEN DECLARING "REL" BUILD
+	// cmd.FlagWithArg("--current-codename ", ctx.Config().PlatformSdkCodename())
 
 	filename := proptools.StringDefault(d.properties.Api_levels_jar_filename, "android.jar")
 
diff --git a/java/java_test.go b/java/java_test.go
index 1b8aec2..bd373c1 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -19,7 +19,6 @@
 	"os"
 	"path/filepath"
 	"reflect"
-	"regexp"
 	"runtime"
 	"strconv"
 	"strings"
@@ -655,306 +654,6 @@
 	})
 }
 
-func TestJavaSdkLibraryImport(t *testing.T) {
-	result := prepareForJavaTest.RunTestWithBp(t, `
-		java_library {
-			name: "foo",
-			srcs: ["a.java"],
-			libs: ["sdklib"],
-			sdk_version: "current",
-		}
-
-		java_library {
-			name: "foo.system",
-			srcs: ["a.java"],
-			libs: ["sdklib"],
-			sdk_version: "system_current",
-		}
-
-		java_library {
-			name: "foo.test",
-			srcs: ["a.java"],
-			libs: ["sdklib"],
-			sdk_version: "test_current",
-		}
-
-		java_sdk_library_import {
-			name: "sdklib",
-			public: {
-				jars: ["a.jar"],
-			},
-			system: {
-				jars: ["b.jar"],
-			},
-			test: {
-				jars: ["c.jar"],
-				stub_srcs: ["c.java"],
-			},
-		}
-		`)
-
-	for _, scope := range []string{"", ".system", ".test"} {
-		fooModule := result.ModuleForTests("foo"+scope, "android_common")
-		javac := fooModule.Rule("javac")
-
-		sdklibStubsJar := result.ModuleForTests("sdklib.stubs"+scope, "android_common").Rule("combineJar").Output
-		android.AssertStringDoesContain(t, "foo classpath", javac.Args["classpath"], sdklibStubsJar.String())
-	}
-
-	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
-		`prebuilt_sdklib.stubs`,
-		`prebuilt_sdklib.stubs.source.test`,
-		`prebuilt_sdklib.stubs.system`,
-		`prebuilt_sdklib.stubs.test`,
-	})
-}
-
-func TestJavaSdkLibraryImport_WithSource(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("sdklib"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "sdklib",
-			srcs: ["a.java"],
-			sdk_version: "none",
-			system_modules: "none",
-			public: {
-				enabled: true,
-			},
-		}
-
-		java_sdk_library_import {
-			name: "sdklib",
-			public: {
-				jars: ["a.jar"],
-			},
-		}
-		`)
-
-	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
-		`dex2oatd`,
-		`prebuilt_sdklib`,
-		`sdklib.impl`,
-		`sdklib.stubs`,
-		`sdklib.stubs.source`,
-		`sdklib.xml`,
-	})
-
-	CheckModuleDependencies(t, result.TestContext, "prebuilt_sdklib", "android_common", []string{
-		`prebuilt_sdklib.stubs`,
-		`sdklib.impl`,
-		// This should be prebuilt_sdklib.stubs but is set to sdklib.stubs because the
-		// dependency is added after prebuilts may have been renamed and so has to use
-		// the renamed name.
-		`sdklib.xml`,
-	})
-}
-
-func TestJavaSdkLibraryImport_Preferred(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("sdklib"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "sdklib",
-			srcs: ["a.java"],
-			sdk_version: "none",
-			system_modules: "none",
-			public: {
-				enabled: true,
-			},
-		}
-
-		java_sdk_library_import {
-			name: "sdklib",
-			prefer: true,
-			public: {
-				jars: ["a.jar"],
-			},
-		}
-		`)
-
-	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
-		`dex2oatd`,
-		`prebuilt_sdklib`,
-		`sdklib.impl`,
-		`sdklib.stubs`,
-		`sdklib.stubs.source`,
-		`sdklib.xml`,
-	})
-
-	CheckModuleDependencies(t, result.TestContext, "prebuilt_sdklib", "android_common", []string{
-		`prebuilt_sdklib.stubs`,
-		`sdklib.impl`,
-		`sdklib.xml`,
-	})
-}
-
-func TestJavaSdkLibraryEnforce(t *testing.T) {
-	partitionToBpOption := func(partition string) string {
-		switch partition {
-		case "system":
-			return ""
-		case "vendor":
-			return "soc_specific: true,"
-		case "product":
-			return "product_specific: true,"
-		default:
-			panic("Invalid partition group name: " + partition)
-		}
-	}
-
-	type testConfigInfo struct {
-		libraryType                string
-		fromPartition              string
-		toPartition                string
-		enforceVendorInterface     bool
-		enforceProductInterface    bool
-		enforceJavaSdkLibraryCheck bool
-		allowList                  []string
-	}
-
-	createPreparer := func(info testConfigInfo) android.FixturePreparer {
-		bpFileTemplate := `
-			java_library {
-				name: "foo",
-				srcs: ["foo.java"],
-				libs: ["bar"],
-				sdk_version: "current",
-				%s
-			}
-
-			%s {
-				name: "bar",
-				srcs: ["bar.java"],
-				sdk_version: "current",
-				%s
-			}
-		`
-
-		bpFile := fmt.Sprintf(bpFileTemplate,
-			partitionToBpOption(info.fromPartition),
-			info.libraryType,
-			partitionToBpOption(info.toPartition))
-
-		return android.GroupFixturePreparers(
-			PrepareForTestWithJavaSdkLibraryFiles,
-			FixtureWithLastReleaseApis("bar"),
-			android.FixtureWithRootAndroidBp(bpFile),
-			android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
-				variables.EnforceProductPartitionInterface = proptools.BoolPtr(info.enforceProductInterface)
-				if info.enforceVendorInterface {
-					variables.DeviceVndkVersion = proptools.StringPtr("current")
-				}
-				variables.EnforceInterPartitionJavaSdkLibrary = proptools.BoolPtr(info.enforceJavaSdkLibraryCheck)
-				variables.InterPartitionJavaLibraryAllowList = info.allowList
-			}),
-		)
-	}
-
-	runTest := func(t *testing.T, info testConfigInfo, expectedErrorPattern string) {
-		t.Run(fmt.Sprintf("%v", info), func(t *testing.T) {
-			errorHandler := android.FixtureExpectsNoErrors
-			if expectedErrorPattern != "" {
-				errorHandler = android.FixtureExpectsAtLeastOneErrorMatchingPattern(expectedErrorPattern)
-			}
-			android.GroupFixturePreparers(
-				prepareForJavaTest,
-				createPreparer(info),
-			).
-				ExtendWithErrorHandler(errorHandler).
-				RunTest(t)
-		})
-	}
-
-	errorMessage := "is not allowed across the partitions"
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "product",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: false,
-	}, "")
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "product",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    false,
-		enforceJavaSdkLibraryCheck: true,
-	}, "")
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "product",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, errorMessage)
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "vendor",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, errorMessage)
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "vendor",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-		allowList:                  []string{"bar"},
-	}, "")
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_library",
-		fromPartition:              "vendor",
-		toPartition:                "product",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, errorMessage)
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_sdk_library",
-		fromPartition:              "product",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, "")
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_sdk_library",
-		fromPartition:              "vendor",
-		toPartition:                "system",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, "")
-
-	runTest(t, testConfigInfo{
-		libraryType:                "java_sdk_library",
-		fromPartition:              "vendor",
-		toPartition:                "product",
-		enforceVendorInterface:     true,
-		enforceProductInterface:    true,
-		enforceJavaSdkLibraryCheck: true,
-	}, "")
-}
-
 func TestDefaults(t *testing.T) {
 	ctx, _ := testJava(t, `
 		java_defaults {
@@ -1411,521 +1110,6 @@
 	})
 }
 
-func TestJavaSdkLibrary(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithPrebuiltApis(map[string][]string{
-			"28": {"foo"},
-			"29": {"foo"},
-			"30": {"bar", "barney", "baz", "betty", "foo", "fred", "quuz", "wilma"},
-		}),
-	).RunTestWithBp(t, `
-		droiddoc_exported_dir {
-			name: "droiddoc-templates-sdk",
-			path: ".",
-		}
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java", "b.java"],
-			api_packages: ["foo"],
-		}
-		java_sdk_library {
-			name: "bar",
-			srcs: ["a.java", "b.java"],
-			api_packages: ["bar"],
-		}
-		java_library {
-			name: "baz",
-			srcs: ["c.java"],
-			libs: ["foo", "bar.stubs"],
-			sdk_version: "system_current",
-		}
-		java_sdk_library {
-			name: "barney",
-			srcs: ["c.java"],
-			api_only: true,
-		}
-		java_sdk_library {
-			name: "betty",
-			srcs: ["c.java"],
-			shared_library: false,
-		}
-		java_sdk_library_import {
-		    name: "quuz",
-				public: {
-					jars: ["c.jar"],
-				},
-		}
-		java_sdk_library_import {
-		    name: "fred",
-				public: {
-					jars: ["b.jar"],
-				},
-		}
-		java_sdk_library_import {
-		    name: "wilma",
-				public: {
-					jars: ["b.jar"],
-				},
-				shared_library: false,
-		}
-		java_library {
-		    name: "qux",
-		    srcs: ["c.java"],
-		    libs: ["baz", "fred", "quuz.stubs", "wilma", "barney", "betty"],
-		    sdk_version: "system_current",
-		}
-		java_library {
-			name: "baz-test",
-			srcs: ["c.java"],
-			libs: ["foo"],
-			sdk_version: "test_current",
-		}
-		java_library {
-			name: "baz-29",
-			srcs: ["c.java"],
-			libs: ["foo"],
-			sdk_version: "system_29",
-		}
-		java_library {
-			name: "baz-module-30",
-			srcs: ["c.java"],
-			libs: ["foo"],
-			sdk_version: "module_30",
-		}
-		`)
-
-	// check the existence of the internal modules
-	result.ModuleForTests("foo", "android_common")
-	result.ModuleForTests(apiScopePublic.stubsLibraryModuleName("foo"), "android_common")
-	result.ModuleForTests(apiScopeSystem.stubsLibraryModuleName("foo"), "android_common")
-	result.ModuleForTests(apiScopeTest.stubsLibraryModuleName("foo"), "android_common")
-	result.ModuleForTests(apiScopePublic.stubsSourceModuleName("foo"), "android_common")
-	result.ModuleForTests(apiScopeSystem.stubsSourceModuleName("foo"), "android_common")
-	result.ModuleForTests(apiScopeTest.stubsSourceModuleName("foo"), "android_common")
-	result.ModuleForTests("foo"+sdkXmlFileSuffix, "android_common")
-	result.ModuleForTests("foo.api.public.28", "")
-	result.ModuleForTests("foo.api.system.28", "")
-	result.ModuleForTests("foo.api.test.28", "")
-
-	bazJavac := result.ModuleForTests("baz", "android_common").Rule("javac")
-	// tests if baz is actually linked to the stubs lib
-	android.AssertStringDoesContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.stubs.system.jar")
-	// ... and not to the impl lib
-	android.AssertStringDoesNotContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.jar")
-	// test if baz is not linked to the system variant of foo
-	android.AssertStringDoesNotContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.stubs.jar")
-
-	bazTestJavac := result.ModuleForTests("baz-test", "android_common").Rule("javac")
-	// tests if baz-test is actually linked to the test stubs lib
-	android.AssertStringDoesContain(t, "baz-test javac classpath", bazTestJavac.Args["classpath"], "foo.stubs.test.jar")
-
-	baz29Javac := result.ModuleForTests("baz-29", "android_common").Rule("javac")
-	// tests if baz-29 is actually linked to the system 29 stubs lib
-	android.AssertStringDoesContain(t, "baz-29 javac classpath", baz29Javac.Args["classpath"], "prebuilts/sdk/29/system/foo.jar")
-
-	bazModule30Javac := result.ModuleForTests("baz-module-30", "android_common").Rule("javac")
-	// tests if "baz-module-30" is actually linked to the module 30 stubs lib
-	android.AssertStringDoesContain(t, "baz-module-30 javac classpath", bazModule30Javac.Args["classpath"], "prebuilts/sdk/30/module-lib/foo.jar")
-
-	// test if baz has exported SDK lib names foo and bar to qux
-	qux := result.ModuleForTests("qux", "android_common")
-	if quxLib, ok := qux.Module().(*Library); ok {
-		sdkLibs := quxLib.ClassLoaderContexts().UsesLibs()
-		android.AssertDeepEquals(t, "qux exports", []string{"foo", "bar", "fred", "quuz"}, sdkLibs)
-	}
-}
-
-func TestJavaSdkLibrary_StubOrImplOnlyLibs(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("sdklib"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "sdklib",
-			srcs: ["a.java"],
-			libs: ["lib"],
-			static_libs: ["static-lib"],
-			impl_only_libs: ["impl-only-lib"],
-			stub_only_libs: ["stub-only-lib"],
-			stub_only_static_libs: ["stub-only-static-lib"],
-		}
-		java_defaults {
-			name: "defaults",
-			srcs: ["a.java"],
-			sdk_version: "current",
-		}
-		java_library { name: "lib", defaults: ["defaults"] }
-		java_library { name: "static-lib", defaults: ["defaults"] }
-		java_library { name: "impl-only-lib", defaults: ["defaults"] }
-		java_library { name: "stub-only-lib", defaults: ["defaults"] }
-		java_library { name: "stub-only-static-lib", defaults: ["defaults"] }
-		`)
-	var expectations = []struct {
-		lib               string
-		on_impl_classpath bool
-		on_stub_classpath bool
-		in_impl_combined  bool
-		in_stub_combined  bool
-	}{
-		{lib: "lib", on_impl_classpath: true},
-		{lib: "static-lib", in_impl_combined: true},
-		{lib: "impl-only-lib", on_impl_classpath: true},
-		{lib: "stub-only-lib", on_stub_classpath: true},
-		{lib: "stub-only-static-lib", in_stub_combined: true},
-	}
-	verify := func(sdklib, dep string, cp, combined bool) {
-		sdklibCp := result.ModuleForTests(sdklib, "android_common").Rule("javac").Args["classpath"]
-		expected := cp || combined // Every combined jar is also on the classpath.
-		android.AssertStringContainsEquals(t, "bad classpath for "+sdklib, sdklibCp, "/"+dep+".jar", expected)
-
-		combineJarInputs := result.ModuleForTests(sdklib, "android_common").Rule("combineJar").Inputs.Strings()
-		depPath := filepath.Join("out", "soong", ".intermediates", dep, "android_common", "turbine-combined", dep+".jar")
-		android.AssertStringListContainsEquals(t, "bad combined inputs for "+sdklib, combineJarInputs, depPath, combined)
-	}
-	for _, expectation := range expectations {
-		verify("sdklib", expectation.lib, expectation.on_impl_classpath, expectation.in_impl_combined)
-		verify("sdklib.impl", expectation.lib, expectation.on_impl_classpath, expectation.in_impl_combined)
-
-		stubName := apiScopePublic.stubsLibraryModuleName("sdklib")
-		verify(stubName, expectation.lib, expectation.on_stub_classpath, expectation.in_stub_combined)
-	}
-}
-
-func TestJavaSdkLibrary_DoNotAccessImplWhenItIsNotBuilt(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java"],
-			api_only: true,
-			public: {
-				enabled: true,
-			},
-		}
-
-		java_library {
-			name: "bar",
-			srcs: ["b.java"],
-			libs: ["foo"],
-		}
-		`)
-
-	// The bar library should depend on the stubs jar.
-	barLibrary := result.ModuleForTests("bar", "android_common").Rule("javac")
-	if expected, actual := `^-classpath .*:out/soong/[^:]*/turbine-combined/foo\.stubs\.jar$`, barLibrary.Args["classpath"]; !regexp.MustCompile(expected).MatchString(actual) {
-		t.Errorf("expected %q, found %#q", expected, actual)
-	}
-}
-
-func TestJavaSdkLibrary_UseSourcesFromAnotherSdkLibrary(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java"],
-			api_packages: ["foo"],
-			public: {
-				enabled: true,
-			},
-		}
-
-		java_library {
-			name: "bar",
-			srcs: ["b.java", ":foo{.public.stubs.source}"],
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_AccessOutputFiles_MissingScope(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).
-		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`"foo" does not provide api scope system`)).
-		RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java"],
-			api_packages: ["foo"],
-			public: {
-				enabled: true,
-			},
-		}
-
-		java_library {
-			name: "bar",
-			srcs: ["b.java", ":foo{.system.stubs.source}"],
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_Deps(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("sdklib"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "sdklib",
-			srcs: ["a.java"],
-			sdk_version: "none",
-			system_modules: "none",
-			public: {
-				enabled: true,
-			},
-		}
-		`)
-
-	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
-		`dex2oatd`,
-		`sdklib.impl`,
-		`sdklib.stubs`,
-		`sdklib.stubs.source`,
-		`sdklib.xml`,
-	})
-}
-
-func TestJavaSdkLibraryImport_AccessOutputFiles(t *testing.T) {
-	prepareForJavaTest.RunTestWithBp(t, `
-		java_sdk_library_import {
-			name: "foo",
-			public: {
-				jars: ["a.jar"],
-				stub_srcs: ["a.java"],
-				current_api: "api/current.txt",
-				removed_api: "api/removed.txt",
-			},
-		}
-
-		java_library {
-			name: "bar",
-			srcs: [":foo{.public.stubs.source}"],
-			java_resources: [
-				":foo{.public.api.txt}",
-				":foo{.public.removed-api.txt}",
-			],
-		}
-		`)
-}
-
-func TestJavaSdkLibraryImport_AccessOutputFiles_Invalid(t *testing.T) {
-	bp := `
-		java_sdk_library_import {
-			name: "foo",
-			public: {
-				jars: ["a.jar"],
-			},
-		}
-		`
-
-	t.Run("stubs.source", func(t *testing.T) {
-		prepareForJavaTest.
-			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`stubs.source not available for api scope public`)).
-			RunTestWithBp(t, bp+`
-				java_library {
-					name: "bar",
-					srcs: [":foo{.public.stubs.source}"],
-					java_resources: [
-						":foo{.public.api.txt}",
-						":foo{.public.removed-api.txt}",
-					],
-				}
-			`)
-	})
-
-	t.Run("api.txt", func(t *testing.T) {
-		prepareForJavaTest.
-			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`api.txt not available for api scope public`)).
-			RunTestWithBp(t, bp+`
-				java_library {
-					name: "bar",
-					srcs: ["a.java"],
-					java_resources: [
-						":foo{.public.api.txt}",
-					],
-				}
-			`)
-	})
-
-	t.Run("removed-api.txt", func(t *testing.T) {
-		prepareForJavaTest.
-			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`removed-api.txt not available for api scope public`)).
-			RunTestWithBp(t, bp+`
-				java_library {
-					name: "bar",
-					srcs: ["a.java"],
-					java_resources: [
-						":foo{.public.removed-api.txt}",
-					],
-				}
-			`)
-	})
-}
-
-func TestJavaSdkLibrary_InvalidScopes(t *testing.T) {
-	prepareForJavaTest.
-		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`module "foo": enabled api scope "system" depends on disabled scope "public"`)).
-		RunTestWithBp(t, `
-			java_sdk_library {
-				name: "foo",
-				srcs: ["a.java", "b.java"],
-				api_packages: ["foo"],
-				// Explicitly disable public to test the check that ensures the set of enabled
-				// scopes is consistent.
-				public: {
-					enabled: false,
-				},
-				system: {
-					enabled: true,
-				},
-			}
-		`)
-}
-
-func TestJavaSdkLibrary_SdkVersion_ForScope(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java", "b.java"],
-			api_packages: ["foo"],
-			system: {
-				enabled: true,
-				sdk_version: "module_current",
-			},
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_ModuleLib(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java", "b.java"],
-			api_packages: ["foo"],
-			system: {
-				enabled: true,
-			},
-			module_lib: {
-				enabled: true,
-			},
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_SystemServer(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java", "b.java"],
-			api_packages: ["foo"],
-			system: {
-				enabled: true,
-			},
-			system_server: {
-				enabled: true,
-			},
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_MissingScope(t *testing.T) {
-	prepareForJavaTest.
-		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`requires api scope module-lib from foo but it only has \[\] available`)).
-		RunTestWithBp(t, `
-			java_sdk_library {
-				name: "foo",
-				srcs: ["a.java"],
-				public: {
-					enabled: false,
-				},
-			}
-
-			java_library {
-				name: "baz",
-				srcs: ["a.java"],
-				libs: ["foo"],
-				sdk_version: "module_current",
-			}
-		`)
-}
-
-func TestJavaSdkLibrary_FallbackScope(t *testing.T) {
-	android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java"],
-			system: {
-				enabled: true,
-			},
-		}
-
-		java_library {
-			name: "baz",
-			srcs: ["a.java"],
-			libs: ["foo"],
-			// foo does not have module-lib scope so it should fallback to system
-			sdk_version: "module_current",
-		}
-		`)
-}
-
-func TestJavaSdkLibrary_DefaultToStubs(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForJavaTest,
-		PrepareForTestWithJavaSdkLibraryFiles,
-		FixtureWithLastReleaseApis("foo"),
-	).RunTestWithBp(t, `
-		java_sdk_library {
-			name: "foo",
-			srcs: ["a.java"],
-			system: {
-				enabled: true,
-			},
-			default_to_stubs: true,
-		}
-
-		java_library {
-			name: "baz",
-			srcs: ["a.java"],
-			libs: ["foo"],
-			// does not have sdk_version set, should fallback to module,
-			// which will then fallback to system because the module scope
-			// is not enabled.
-		}
-		`)
-	// The baz library should depend on the system stubs jar.
-	bazLibrary := result.ModuleForTests("baz", "android_common").Rule("javac")
-	if expected, actual := `^-classpath .*:out/soong/[^:]*/turbine-combined/foo\.stubs.system\.jar$`, bazLibrary.Args["classpath"]; !regexp.MustCompile(expected).MatchString(actual) {
-		t.Errorf("expected %q, found %#q", expected, actual)
-	}
-}
-
 var compilerFlagsTestCases = []struct {
 	in  string
 	out bool
diff --git a/java/sdk_library.go b/java/sdk_library.go
index 3f87727..aec113c 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -457,6 +457,11 @@
 	// * API incompatibilities baseline filegroup -> <dist-stem>-incompatibilities.api.<scope>.latest
 	Dist_stem *string
 
+	// The subdirectory for the artifacts that are copied to the dist directory.  If not specified
+	// then defaults to "android".  Should be set to "android" for anything that should be published
+	// in the public Android SDK.
+	Dist_group *string
+
 	// A compatibility mode that allows historical API-tracking files to not exist.
 	// Do not use.
 	Unsafe_ignore_missing_latest_api bool
@@ -1198,12 +1203,10 @@
 
 // The dist path of the stub artifacts
 func (module *SdkLibrary) apiDistPath(apiScope *apiScope) string {
-	if module.ModuleBase.Owner() != "" {
-		return path.Join("apistubs", module.ModuleBase.Owner(), apiScope.name)
-	} else if Bool(module.sdkLibraryProperties.Core_lib) {
+	if Bool(module.sdkLibraryProperties.Core_lib) {
 		return path.Join("apistubs", "core", apiScope.name)
 	} else {
-		return path.Join("apistubs", "android", apiScope.name)
+		return path.Join("apistubs", module.distGroup(), apiScope.name)
 	}
 }
 
@@ -1228,6 +1231,19 @@
 	return proptools.StringDefault(module.sdkLibraryProperties.Dist_stem, module.BaseModuleName())
 }
 
+// distGroup returns the subdirectory of the dist path of the stub artifacts.
+func (module *SdkLibrary) distGroup() string {
+	if group := proptools.String(module.sdkLibraryProperties.Dist_group); group != "" {
+		return group
+	}
+	// TODO(b/186723288): Remove this once everything uses dist_group.
+	if owner := module.ModuleBase.Owner(); owner != "" {
+		return owner
+	}
+	// TODO(b/186723288): Make this "unknown".
+	return "android"
+}
+
 func (module *SdkLibrary) latestApiFilegroupName(apiScope *apiScope) string {
 	return ":" + module.distStem() + ".api." + apiScope.name + ".latest"
 }
diff --git a/java/sdk_library_test.go b/java/sdk_library_test.go
new file mode 100644
index 0000000..0fe6e72
--- /dev/null
+++ b/java/sdk_library_test.go
@@ -0,0 +1,931 @@
+// Copyright 2021 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 (
+	"android/soong/android"
+	"fmt"
+	"path/filepath"
+	"regexp"
+	"testing"
+
+	"github.com/google/blueprint/proptools"
+)
+
+func TestJavaSdkLibrary(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithPrebuiltApis(map[string][]string{
+			"28": {"foo"},
+			"29": {"foo"},
+			"30": {"bar", "barney", "baz", "betty", "foo", "fred", "quuz", "wilma"},
+		}),
+	).RunTestWithBp(t, `
+		droiddoc_exported_dir {
+			name: "droiddoc-templates-sdk",
+			path: ".",
+		}
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["foo"],
+		}
+		java_sdk_library {
+			name: "bar",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["bar"],
+		}
+		java_library {
+			name: "baz",
+			srcs: ["c.java"],
+			libs: ["foo", "bar.stubs"],
+			sdk_version: "system_current",
+		}
+		java_sdk_library {
+			name: "barney",
+			srcs: ["c.java"],
+			api_only: true,
+		}
+		java_sdk_library {
+			name: "betty",
+			srcs: ["c.java"],
+			shared_library: false,
+		}
+		java_sdk_library_import {
+		    name: "quuz",
+				public: {
+					jars: ["c.jar"],
+				},
+		}
+		java_sdk_library_import {
+		    name: "fred",
+				public: {
+					jars: ["b.jar"],
+				},
+		}
+		java_sdk_library_import {
+		    name: "wilma",
+				public: {
+					jars: ["b.jar"],
+				},
+				shared_library: false,
+		}
+		java_library {
+		    name: "qux",
+		    srcs: ["c.java"],
+		    libs: ["baz", "fred", "quuz.stubs", "wilma", "barney", "betty"],
+		    sdk_version: "system_current",
+		}
+		java_library {
+			name: "baz-test",
+			srcs: ["c.java"],
+			libs: ["foo"],
+			sdk_version: "test_current",
+		}
+		java_library {
+			name: "baz-29",
+			srcs: ["c.java"],
+			libs: ["foo"],
+			sdk_version: "system_29",
+		}
+		java_library {
+			name: "baz-module-30",
+			srcs: ["c.java"],
+			libs: ["foo"],
+			sdk_version: "module_30",
+		}
+		`)
+
+	// check the existence of the internal modules
+	result.ModuleForTests("foo", "android_common")
+	result.ModuleForTests(apiScopePublic.stubsLibraryModuleName("foo"), "android_common")
+	result.ModuleForTests(apiScopeSystem.stubsLibraryModuleName("foo"), "android_common")
+	result.ModuleForTests(apiScopeTest.stubsLibraryModuleName("foo"), "android_common")
+	result.ModuleForTests(apiScopePublic.stubsSourceModuleName("foo"), "android_common")
+	result.ModuleForTests(apiScopeSystem.stubsSourceModuleName("foo"), "android_common")
+	result.ModuleForTests(apiScopeTest.stubsSourceModuleName("foo"), "android_common")
+	result.ModuleForTests("foo"+sdkXmlFileSuffix, "android_common")
+	result.ModuleForTests("foo.api.public.28", "")
+	result.ModuleForTests("foo.api.system.28", "")
+	result.ModuleForTests("foo.api.test.28", "")
+
+	bazJavac := result.ModuleForTests("baz", "android_common").Rule("javac")
+	// tests if baz is actually linked to the stubs lib
+	android.AssertStringDoesContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.stubs.system.jar")
+	// ... and not to the impl lib
+	android.AssertStringDoesNotContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.jar")
+	// test if baz is not linked to the system variant of foo
+	android.AssertStringDoesNotContain(t, "baz javac classpath", bazJavac.Args["classpath"], "foo.stubs.jar")
+
+	bazTestJavac := result.ModuleForTests("baz-test", "android_common").Rule("javac")
+	// tests if baz-test is actually linked to the test stubs lib
+	android.AssertStringDoesContain(t, "baz-test javac classpath", bazTestJavac.Args["classpath"], "foo.stubs.test.jar")
+
+	baz29Javac := result.ModuleForTests("baz-29", "android_common").Rule("javac")
+	// tests if baz-29 is actually linked to the system 29 stubs lib
+	android.AssertStringDoesContain(t, "baz-29 javac classpath", baz29Javac.Args["classpath"], "prebuilts/sdk/29/system/foo.jar")
+
+	bazModule30Javac := result.ModuleForTests("baz-module-30", "android_common").Rule("javac")
+	// tests if "baz-module-30" is actually linked to the module 30 stubs lib
+	android.AssertStringDoesContain(t, "baz-module-30 javac classpath", bazModule30Javac.Args["classpath"], "prebuilts/sdk/30/module-lib/foo.jar")
+
+	// test if baz has exported SDK lib names foo and bar to qux
+	qux := result.ModuleForTests("qux", "android_common")
+	if quxLib, ok := qux.Module().(*Library); ok {
+		sdkLibs := quxLib.ClassLoaderContexts().UsesLibs()
+		android.AssertDeepEquals(t, "qux exports", []string{"foo", "bar", "fred", "quuz"}, sdkLibs)
+	}
+}
+
+func TestJavaSdkLibrary_StubOrImplOnlyLibs(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("sdklib"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "sdklib",
+			srcs: ["a.java"],
+			libs: ["lib"],
+			static_libs: ["static-lib"],
+			impl_only_libs: ["impl-only-lib"],
+			stub_only_libs: ["stub-only-lib"],
+			stub_only_static_libs: ["stub-only-static-lib"],
+		}
+		java_defaults {
+			name: "defaults",
+			srcs: ["a.java"],
+			sdk_version: "current",
+		}
+		java_library { name: "lib", defaults: ["defaults"] }
+		java_library { name: "static-lib", defaults: ["defaults"] }
+		java_library { name: "impl-only-lib", defaults: ["defaults"] }
+		java_library { name: "stub-only-lib", defaults: ["defaults"] }
+		java_library { name: "stub-only-static-lib", defaults: ["defaults"] }
+		`)
+	var expectations = []struct {
+		lib               string
+		on_impl_classpath bool
+		on_stub_classpath bool
+		in_impl_combined  bool
+		in_stub_combined  bool
+	}{
+		{lib: "lib", on_impl_classpath: true},
+		{lib: "static-lib", in_impl_combined: true},
+		{lib: "impl-only-lib", on_impl_classpath: true},
+		{lib: "stub-only-lib", on_stub_classpath: true},
+		{lib: "stub-only-static-lib", in_stub_combined: true},
+	}
+	verify := func(sdklib, dep string, cp, combined bool) {
+		sdklibCp := result.ModuleForTests(sdklib, "android_common").Rule("javac").Args["classpath"]
+		expected := cp || combined // Every combined jar is also on the classpath.
+		android.AssertStringContainsEquals(t, "bad classpath for "+sdklib, sdklibCp, "/"+dep+".jar", expected)
+
+		combineJarInputs := result.ModuleForTests(sdklib, "android_common").Rule("combineJar").Inputs.Strings()
+		depPath := filepath.Join("out", "soong", ".intermediates", dep, "android_common", "turbine-combined", dep+".jar")
+		android.AssertStringListContainsEquals(t, "bad combined inputs for "+sdklib, combineJarInputs, depPath, combined)
+	}
+	for _, expectation := range expectations {
+		verify("sdklib", expectation.lib, expectation.on_impl_classpath, expectation.in_impl_combined)
+		verify("sdklib.impl", expectation.lib, expectation.on_impl_classpath, expectation.in_impl_combined)
+
+		stubName := apiScopePublic.stubsLibraryModuleName("sdklib")
+		verify(stubName, expectation.lib, expectation.on_stub_classpath, expectation.in_stub_combined)
+	}
+}
+
+func TestJavaSdkLibrary_DoNotAccessImplWhenItIsNotBuilt(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			api_only: true,
+			public: {
+				enabled: true,
+			},
+		}
+
+		java_library {
+			name: "bar",
+			srcs: ["b.java"],
+			libs: ["foo"],
+		}
+		`)
+
+	// The bar library should depend on the stubs jar.
+	barLibrary := result.ModuleForTests("bar", "android_common").Rule("javac")
+	if expected, actual := `^-classpath .*:out/soong/[^:]*/turbine-combined/foo\.stubs\.jar$`, barLibrary.Args["classpath"]; !regexp.MustCompile(expected).MatchString(actual) {
+		t.Errorf("expected %q, found %#q", expected, actual)
+	}
+}
+
+func TestJavaSdkLibrary_UseSourcesFromAnotherSdkLibrary(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			api_packages: ["foo"],
+			public: {
+				enabled: true,
+			},
+		}
+
+		java_library {
+			name: "bar",
+			srcs: ["b.java", ":foo{.public.stubs.source}"],
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_AccessOutputFiles_MissingScope(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).
+		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`"foo" does not provide api scope system`)).
+		RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			api_packages: ["foo"],
+			public: {
+				enabled: true,
+			},
+		}
+
+		java_library {
+			name: "bar",
+			srcs: ["b.java", ":foo{.system.stubs.source}"],
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_Deps(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("sdklib"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "sdklib",
+			srcs: ["a.java"],
+			sdk_version: "none",
+			system_modules: "none",
+			public: {
+				enabled: true,
+			},
+		}
+		`)
+
+	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
+		`dex2oatd`,
+		`sdklib.impl`,
+		`sdklib.stubs`,
+		`sdklib.stubs.source`,
+		`sdklib.xml`,
+	})
+}
+
+func TestJavaSdkLibraryImport_AccessOutputFiles(t *testing.T) {
+	prepareForJavaTest.RunTestWithBp(t, `
+		java_sdk_library_import {
+			name: "foo",
+			public: {
+				jars: ["a.jar"],
+				stub_srcs: ["a.java"],
+				current_api: "api/current.txt",
+				removed_api: "api/removed.txt",
+			},
+		}
+
+		java_library {
+			name: "bar",
+			srcs: [":foo{.public.stubs.source}"],
+			java_resources: [
+				":foo{.public.api.txt}",
+				":foo{.public.removed-api.txt}",
+			],
+		}
+		`)
+}
+
+func TestJavaSdkLibraryImport_AccessOutputFiles_Invalid(t *testing.T) {
+	bp := `
+		java_sdk_library_import {
+			name: "foo",
+			public: {
+				jars: ["a.jar"],
+			},
+		}
+		`
+
+	t.Run("stubs.source", func(t *testing.T) {
+		prepareForJavaTest.
+			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`stubs.source not available for api scope public`)).
+			RunTestWithBp(t, bp+`
+				java_library {
+					name: "bar",
+					srcs: [":foo{.public.stubs.source}"],
+					java_resources: [
+						":foo{.public.api.txt}",
+						":foo{.public.removed-api.txt}",
+					],
+				}
+			`)
+	})
+
+	t.Run("api.txt", func(t *testing.T) {
+		prepareForJavaTest.
+			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`api.txt not available for api scope public`)).
+			RunTestWithBp(t, bp+`
+				java_library {
+					name: "bar",
+					srcs: ["a.java"],
+					java_resources: [
+						":foo{.public.api.txt}",
+					],
+				}
+			`)
+	})
+
+	t.Run("removed-api.txt", func(t *testing.T) {
+		prepareForJavaTest.
+			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`removed-api.txt not available for api scope public`)).
+			RunTestWithBp(t, bp+`
+				java_library {
+					name: "bar",
+					srcs: ["a.java"],
+					java_resources: [
+						":foo{.public.removed-api.txt}",
+					],
+				}
+			`)
+	})
+}
+
+func TestJavaSdkLibrary_InvalidScopes(t *testing.T) {
+	prepareForJavaTest.
+		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`module "foo": enabled api scope "system" depends on disabled scope "public"`)).
+		RunTestWithBp(t, `
+			java_sdk_library {
+				name: "foo",
+				srcs: ["a.java", "b.java"],
+				api_packages: ["foo"],
+				// Explicitly disable public to test the check that ensures the set of enabled
+				// scopes is consistent.
+				public: {
+					enabled: false,
+				},
+				system: {
+					enabled: true,
+				},
+			}
+		`)
+}
+
+func TestJavaSdkLibrary_SdkVersion_ForScope(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["foo"],
+			system: {
+				enabled: true,
+				sdk_version: "module_current",
+			},
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_ModuleLib(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["foo"],
+			system: {
+				enabled: true,
+			},
+			module_lib: {
+				enabled: true,
+			},
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_SystemServer(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["foo"],
+			system: {
+				enabled: true,
+			},
+			system_server: {
+				enabled: true,
+			},
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_MissingScope(t *testing.T) {
+	prepareForJavaTest.
+		ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`requires api scope module-lib from foo but it only has \[\] available`)).
+		RunTestWithBp(t, `
+			java_sdk_library {
+				name: "foo",
+				srcs: ["a.java"],
+				public: {
+					enabled: false,
+				},
+			}
+
+			java_library {
+				name: "baz",
+				srcs: ["a.java"],
+				libs: ["foo"],
+				sdk_version: "module_current",
+			}
+		`)
+}
+
+func TestJavaSdkLibrary_FallbackScope(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			system: {
+				enabled: true,
+			},
+		}
+
+		java_library {
+			name: "baz",
+			srcs: ["a.java"],
+			libs: ["foo"],
+			// foo does not have module-lib scope so it should fallback to system
+			sdk_version: "module_current",
+		}
+		`)
+}
+
+func TestJavaSdkLibrary_DefaultToStubs(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("foo"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java"],
+			system: {
+				enabled: true,
+			},
+			default_to_stubs: true,
+		}
+
+		java_library {
+			name: "baz",
+			srcs: ["a.java"],
+			libs: ["foo"],
+			// does not have sdk_version set, should fallback to module,
+			// which will then fallback to system because the module scope
+			// is not enabled.
+		}
+		`)
+	// The baz library should depend on the system stubs jar.
+	bazLibrary := result.ModuleForTests("baz", "android_common").Rule("javac")
+	if expected, actual := `^-classpath .*:out/soong/[^:]*/turbine-combined/foo\.stubs.system\.jar$`, bazLibrary.Args["classpath"]; !regexp.MustCompile(expected).MatchString(actual) {
+		t.Errorf("expected %q, found %#q", expected, actual)
+	}
+}
+
+func TestJavaSdkLibraryImport(t *testing.T) {
+	result := prepareForJavaTest.RunTestWithBp(t, `
+		java_library {
+			name: "foo",
+			srcs: ["a.java"],
+			libs: ["sdklib"],
+			sdk_version: "current",
+		}
+
+		java_library {
+			name: "foo.system",
+			srcs: ["a.java"],
+			libs: ["sdklib"],
+			sdk_version: "system_current",
+		}
+
+		java_library {
+			name: "foo.test",
+			srcs: ["a.java"],
+			libs: ["sdklib"],
+			sdk_version: "test_current",
+		}
+
+		java_sdk_library_import {
+			name: "sdklib",
+			public: {
+				jars: ["a.jar"],
+			},
+			system: {
+				jars: ["b.jar"],
+			},
+			test: {
+				jars: ["c.jar"],
+				stub_srcs: ["c.java"],
+			},
+		}
+		`)
+
+	for _, scope := range []string{"", ".system", ".test"} {
+		fooModule := result.ModuleForTests("foo"+scope, "android_common")
+		javac := fooModule.Rule("javac")
+
+		sdklibStubsJar := result.ModuleForTests("sdklib.stubs"+scope, "android_common").Rule("combineJar").Output
+		android.AssertStringDoesContain(t, "foo classpath", javac.Args["classpath"], sdklibStubsJar.String())
+	}
+
+	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
+		`prebuilt_sdklib.stubs`,
+		`prebuilt_sdklib.stubs.source.test`,
+		`prebuilt_sdklib.stubs.system`,
+		`prebuilt_sdklib.stubs.test`,
+	})
+}
+
+func TestJavaSdkLibraryImport_WithSource(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("sdklib"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "sdklib",
+			srcs: ["a.java"],
+			sdk_version: "none",
+			system_modules: "none",
+			public: {
+				enabled: true,
+			},
+		}
+
+		java_sdk_library_import {
+			name: "sdklib",
+			public: {
+				jars: ["a.jar"],
+			},
+		}
+		`)
+
+	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
+		`dex2oatd`,
+		`prebuilt_sdklib`,
+		`sdklib.impl`,
+		`sdklib.stubs`,
+		`sdklib.stubs.source`,
+		`sdklib.xml`,
+	})
+
+	CheckModuleDependencies(t, result.TestContext, "prebuilt_sdklib", "android_common", []string{
+		`prebuilt_sdklib.stubs`,
+		`sdklib.impl`,
+		// This should be prebuilt_sdklib.stubs but is set to sdklib.stubs because the
+		// dependency is added after prebuilts may have been renamed and so has to use
+		// the renamed name.
+		`sdklib.xml`,
+	})
+}
+
+func TestJavaSdkLibraryImport_Preferred(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("sdklib"),
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "sdklib",
+			srcs: ["a.java"],
+			sdk_version: "none",
+			system_modules: "none",
+			public: {
+				enabled: true,
+			},
+		}
+
+		java_sdk_library_import {
+			name: "sdklib",
+			prefer: true,
+			public: {
+				jars: ["a.jar"],
+			},
+		}
+		`)
+
+	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
+		`dex2oatd`,
+		`prebuilt_sdklib`,
+		`sdklib.impl`,
+		`sdklib.stubs`,
+		`sdklib.stubs.source`,
+		`sdklib.xml`,
+	})
+
+	CheckModuleDependencies(t, result.TestContext, "prebuilt_sdklib", "android_common", []string{
+		`prebuilt_sdklib.stubs`,
+		`sdklib.impl`,
+		`sdklib.xml`,
+	})
+}
+
+func TestJavaSdkLibraryEnforce(t *testing.T) {
+	partitionToBpOption := func(partition string) string {
+		switch partition {
+		case "system":
+			return ""
+		case "vendor":
+			return "soc_specific: true,"
+		case "product":
+			return "product_specific: true,"
+		default:
+			panic("Invalid partition group name: " + partition)
+		}
+	}
+
+	type testConfigInfo struct {
+		libraryType                string
+		fromPartition              string
+		toPartition                string
+		enforceVendorInterface     bool
+		enforceProductInterface    bool
+		enforceJavaSdkLibraryCheck bool
+		allowList                  []string
+	}
+
+	createPreparer := func(info testConfigInfo) android.FixturePreparer {
+		bpFileTemplate := `
+			java_library {
+				name: "foo",
+				srcs: ["foo.java"],
+				libs: ["bar"],
+				sdk_version: "current",
+				%s
+			}
+
+			%s {
+				name: "bar",
+				srcs: ["bar.java"],
+				sdk_version: "current",
+				%s
+			}
+		`
+
+		bpFile := fmt.Sprintf(bpFileTemplate,
+			partitionToBpOption(info.fromPartition),
+			info.libraryType,
+			partitionToBpOption(info.toPartition))
+
+		return android.GroupFixturePreparers(
+			PrepareForTestWithJavaSdkLibraryFiles,
+			FixtureWithLastReleaseApis("bar"),
+			android.FixtureWithRootAndroidBp(bpFile),
+			android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+				variables.EnforceProductPartitionInterface = proptools.BoolPtr(info.enforceProductInterface)
+				if info.enforceVendorInterface {
+					variables.DeviceVndkVersion = proptools.StringPtr("current")
+				}
+				variables.EnforceInterPartitionJavaSdkLibrary = proptools.BoolPtr(info.enforceJavaSdkLibraryCheck)
+				variables.InterPartitionJavaLibraryAllowList = info.allowList
+			}),
+		)
+	}
+
+	runTest := func(t *testing.T, info testConfigInfo, expectedErrorPattern string) {
+		t.Run(fmt.Sprintf("%v", info), func(t *testing.T) {
+			errorHandler := android.FixtureExpectsNoErrors
+			if expectedErrorPattern != "" {
+				errorHandler = android.FixtureExpectsAtLeastOneErrorMatchingPattern(expectedErrorPattern)
+			}
+			android.GroupFixturePreparers(
+				prepareForJavaTest,
+				createPreparer(info),
+			).
+				ExtendWithErrorHandler(errorHandler).
+				RunTest(t)
+		})
+	}
+
+	errorMessage := "is not allowed across the partitions"
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "product",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: false,
+	}, "")
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "product",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    false,
+		enforceJavaSdkLibraryCheck: true,
+	}, "")
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "product",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, errorMessage)
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "vendor",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, errorMessage)
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "vendor",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+		allowList:                  []string{"bar"},
+	}, "")
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_library",
+		fromPartition:              "vendor",
+		toPartition:                "product",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, errorMessage)
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_sdk_library",
+		fromPartition:              "product",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, "")
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_sdk_library",
+		fromPartition:              "vendor",
+		toPartition:                "system",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, "")
+
+	runTest(t, testConfigInfo{
+		libraryType:                "java_sdk_library",
+		fromPartition:              "vendor",
+		toPartition:                "product",
+		enforceVendorInterface:     true,
+		enforceProductInterface:    true,
+		enforceJavaSdkLibraryCheck: true,
+	}, "")
+}
+
+func TestJavaSdkLibraryDist(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		PrepareForTestWithJavaBuildComponents,
+		PrepareForTestWithJavaDefaultModules,
+		PrepareForTestWithJavaSdkLibraryFiles,
+	).RunTestWithBp(t, `
+		java_sdk_library {
+			name: "sdklib_no_owner",
+			unsafe_ignore_missing_latest_api: true,
+			srcs: ["foo.java"],
+		}
+
+		java_sdk_library {
+			name: "sdklib_group_foo",
+			unsafe_ignore_missing_latest_api: true,
+			srcs: ["foo.java"],
+			dist_group: "foo",
+		}
+
+		java_sdk_library {
+			name: "sdklib_owner_foo",
+			unsafe_ignore_missing_latest_api: true,
+			srcs: ["foo.java"],
+			owner: "foo",
+		}
+
+		java_sdk_library {
+			name: "sdklib_stem_foo",
+			unsafe_ignore_missing_latest_api: true,
+			srcs: ["foo.java"],
+			dist_stem: "foo",
+		}
+
+		java_sdk_library {
+			name: "sdklib_core_lib",
+			unsafe_ignore_missing_latest_api: true,
+			srcs: ["foo.java"],
+			core_lib: true,
+		}
+	`)
+
+	type testCase struct {
+		module   string
+		distDir  string
+		distStem string
+	}
+	testCases := []testCase{
+		{
+			module:   "sdklib_no_owner",
+			distDir:  "apistubs/android/public",
+			distStem: "sdklib_no_owner.jar",
+		},
+		{
+			module:   "sdklib_group_foo",
+			distDir:  "apistubs/foo/public",
+			distStem: "sdklib_group_foo.jar",
+		},
+		{
+			module:   "sdklib_owner_foo",
+			distDir:  "apistubs/foo/public",
+			distStem: "sdklib_owner_foo.jar",
+		},
+		{
+			module:   "sdklib_stem_foo",
+			distDir:  "apistubs/android/public",
+			distStem: "foo.jar",
+		},
+		{
+			module:   "sdklib_core_lib",
+			distDir:  "apistubs/core/public",
+			distStem: "sdklib_core_lib.jar",
+		},
+	}
+
+	for _, tt := range testCases {
+		t.Run(tt.module, func(t *testing.T) {
+			m := result.ModuleForTests(tt.module+".stubs", "android_common").Module().(*Library)
+			dists := m.Dists()
+			if len(dists) != 1 {
+				t.Fatalf("expected exactly 1 dist entry, got %d", len(dists))
+			}
+			if g, w := String(dists[0].Dir), tt.distDir; g != w {
+				t.Errorf("expected dist dir %q, got %q", w, g)
+			}
+			if g, w := String(dists[0].Dest), tt.distStem; g != w {
+				t.Errorf("expected dist stem %q, got %q", w, g)
+			}
+		})
+	}
+}