diff --git a/sdk/member_trait_test.go b/sdk/member_trait_test.go
new file mode 100644
index 0000000..a3db189
--- /dev/null
+++ b/sdk/member_trait_test.go
@@ -0,0 +1,287 @@
+// 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 sdk
+
+import (
+	"fmt"
+	"path/filepath"
+	"testing"
+
+	"android/soong/android"
+	"android/soong/java"
+	"github.com/google/blueprint"
+)
+
+type fakeMemberTrait struct {
+	android.SdkMemberTraitBase
+}
+
+type fakeMemberType struct {
+	android.SdkMemberTypeBase
+}
+
+func (t *fakeMemberType) AddDependencies(ctx android.SdkDependencyContext, dependencyTag blueprint.DependencyTag, names []string) {
+	for _, name := range names {
+		ctx.AddVariationDependencies(nil, dependencyTag, name)
+
+		if ctx.RequiresTrait(name, extraTrait) {
+			ctx.AddVariationDependencies(nil, dependencyTag, name+"_extra")
+		}
+		if ctx.RequiresTrait(name, specialTrait) {
+			ctx.AddVariationDependencies(nil, dependencyTag, name+"_special")
+		}
+	}
+}
+
+func (t *fakeMemberType) IsInstance(module android.Module) bool {
+	return true
+}
+
+func (t *fakeMemberType) AddPrebuiltModule(ctx android.SdkMemberContext, member android.SdkMember) android.BpModule {
+	moduleType := "java_import"
+	if ctx.RequiresTrait(extraTrait) {
+		moduleType = "java_test_import"
+	}
+	return ctx.SnapshotBuilder().AddPrebuiltModule(member, moduleType)
+}
+
+func (t *fakeMemberType) CreateVariantPropertiesStruct() android.SdkMemberProperties {
+	return &fakeMemberTypeProperties{}
+}
+
+type fakeMemberTypeProperties struct {
+	android.SdkMemberPropertiesBase
+
+	path android.Path
+}
+
+func (t *fakeMemberTypeProperties) PopulateFromVariant(ctx android.SdkMemberContext, variant android.Module) {
+	headerJars := variant.(java.ApexDependency).HeaderJars()
+	if len(headerJars) != 1 {
+		panic(fmt.Errorf("there must be only one header jar from %q", variant.Name()))
+	}
+
+	t.path = headerJars[0]
+}
+
+func (t *fakeMemberTypeProperties) AddToPropertySet(ctx android.SdkMemberContext, propertySet android.BpPropertySet) {
+	if t.path != nil {
+		relative := filepath.Join("javalibs", t.path.Base())
+		ctx.SnapshotBuilder().CopyToSnapshot(t.path, relative)
+		propertySet.AddProperty("jars", []string{relative})
+	}
+}
+
+var (
+	extraTrait = &fakeMemberTrait{
+		SdkMemberTraitBase: android.SdkMemberTraitBase{
+			PropertyName: "extra",
+		},
+	}
+
+	specialTrait = &fakeMemberTrait{
+		SdkMemberTraitBase: android.SdkMemberTraitBase{
+			PropertyName: "special",
+		},
+	}
+
+	fakeType = &fakeMemberType{
+		SdkMemberTypeBase: android.SdkMemberTypeBase{
+			PropertyName: "fake_members",
+			SupportsSdk:  true,
+			Traits: []android.SdkMemberTrait{
+				extraTrait,
+				specialTrait,
+			},
+		},
+	}
+)
+
+func init() {
+	android.RegisterSdkMemberTrait(extraTrait)
+	android.RegisterSdkMemberTrait(specialTrait)
+	android.RegisterSdkMemberType(fakeType)
+}
+
+func TestBasicTrait_WithoutTrait(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForSdkTestWithJava,
+		android.FixtureWithRootAndroidBp(`
+			sdk {
+				name: "mysdk",
+				fake_members: ["myjavalib"],
+			}
+
+			java_library {
+				name: "myjavalib",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+		`),
+	).RunTest(t)
+
+	CheckSnapshot(t, result, "mysdk", "",
+		checkUnversionedAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+java_import {
+    name: "myjavalib",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/myjavalib.jar"],
+}
+`),
+		checkVersionedAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+java_import {
+    name: "mysdk_myjavalib@current",
+    sdk_member_name: "myjavalib",
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/myjavalib.jar"],
+}
+
+sdk_snapshot {
+    name: "mysdk@current",
+    visibility: ["//visibility:public"],
+    fake_members: ["mysdk_myjavalib@current"],
+}
+`),
+	)
+}
+
+func TestBasicTrait_MultipleTraits(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForSdkTestWithJava,
+		android.FixtureWithRootAndroidBp(`
+			sdk {
+				name: "mysdk",
+				fake_members: ["myjavalib", "anotherjavalib"],
+				traits: {
+					extra: ["myjavalib"],
+					special: ["myjavalib", "anotherjavalib"],
+				},
+			}
+
+			java_library {
+				name: "myjavalib",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+
+			java_library {
+				name: "myjavalib_extra",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+
+			java_library {
+				name: "myjavalib_special",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+
+			java_library {
+				name: "anotherjavalib",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+
+			java_library {
+				name: "anotherjavalib_special",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+		`),
+	).RunTest(t)
+
+	CheckSnapshot(t, result, "mysdk", "",
+		checkUnversionedAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+java_test_import {
+    name: "myjavalib",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/myjavalib.jar"],
+}
+
+java_import {
+    name: "myjavalib_extra",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/myjavalib_extra.jar"],
+}
+
+java_import {
+    name: "myjavalib_special",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/myjavalib_special.jar"],
+}
+
+java_import {
+    name: "anotherjavalib",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/anotherjavalib.jar"],
+}
+
+java_import {
+    name: "anotherjavalib_special",
+    prefer: false,
+    visibility: ["//visibility:public"],
+    apex_available: ["//apex_available:platform"],
+    jars: ["javalibs/anotherjavalib_special.jar"],
+}
+`),
+	)
+}
+
+func TestTraitUnsupportedByMemberType(t *testing.T) {
+	android.GroupFixturePreparers(
+		prepareForSdkTestWithJava,
+		android.FixtureWithRootAndroidBp(`
+			sdk {
+				name: "mysdk",
+				java_header_libs: ["myjavalib"],
+				traits: {
+					extra: ["myjavalib"],
+				},
+			}
+
+			java_library {
+				name: "myjavalib",
+				srcs: ["Test.java"],
+				system_modules: "none",
+				sdk_version: "none",
+			}
+		`),
+	).ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(
+		`\Qsdk member "myjavalib" has traits [extra] that are unsupported by its member type "java_header_libs"\E`)).
+		RunTest(t)
+}