Create @RestrictedFor annotation

The annotation will be used to annotate classes and methods that are
restricted in certain environments.

Bug: 320445933
Test: atest AndroidAnnotationTests
Change-Id: I61498486641ab5a6b0510e112c7ef22e60090a17

4 files changed, 223 insertions, 0 deletions

diff --git a/java/android/annotation/RestrictedFor.java b/java/android/annotation/RestrictedFor.java
new file mode 100644
index 0000000..94a8895
--- /dev/null
+++ b/java/android/annotation/RestrictedFor.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2024 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 android.annotation;
+
+
+import static java.lang.annotation.ElementType.TYPE;
+
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates if an API is restricted in certain environments.
+ *
+ * <p>
+ * The explicit annotation aids in surfacing the restriction to the developers of the environments
+ * in multiple ways:
+ * </p>
+ *
+ * <ul>
+ * <li>Metalava will consume these annotations to generate appropriate javadocs.</li>
+ * <li>Linters will consume these annotation to show warning to developers on their IDE.</li>
+ * <li>Tests will consume these annotation to verify restricted APIs have been annotated.</li>
+ * </ul>
+ *
+ * @hide
+ */
+@Target({TYPE})
+@Retention(RetentionPolicy.RUNTIME)
+@Repeatable(RestrictedFor.Container.class)
+public @interface RestrictedFor {
+
+    /** List of environments where the entity is restricted. */
+    Environment[] environments();
+
+    /**
+     * SDK version since when the restriction started.
+     *
+     * Possible values are defined in {@link android.os.Build.VERSION_CODES}.
+     */
+    int from();
+
+    enum Environment {
+        /**
+         * See {@link android.app.sdksandbox.SdkSandboxManager}
+         */
+        SDK_SANDBOX {
+            @Override
+            public String toString() {
+                return "SDK Runtime";
+            }
+        }
+    }
+
+    /**
+     * Container for {@link RestrictedFor} that allows it to be applied repeatedly to types.
+     */
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(TYPE)
+    @interface Container {
+        RestrictedFor[] value();
+    }
+}
diff --git a/javatests/android/annotation/Android.bp b/javatests/android/annotation/Android.bp
new file mode 100644
index 0000000..f793cbb
--- /dev/null
+++ b/javatests/android/annotation/Android.bp
@@ -0,0 +1,34 @@
+// Copyright (C) 2024 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 {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+android_test {
+    name: "AndroidAnnotationTests",
+    sdk_version: "module_current",
+    srcs: ["*.java"],
+    static_libs: [
+        "androidx.test.rules",
+        "androidx.test.runner",
+        "framework-annotations-lib",
+        "truth",
+    ],
+    libs: [
+        "android.test.runner",
+        "framework-annotations-lib",
+    ],
+    test_suites: ["general-tests"],
+}
diff --git a/javatests/android/annotation/AndroidManifest.xml b/javatests/android/annotation/AndroidManifest.xml
new file mode 100644
index 0000000..5284aa1
--- /dev/null
+++ b/javatests/android/annotation/AndroidManifest.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2022 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.
+  -->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="android.annotation.test">
+
+    <instrumentation android:name="androidx.test.runner.AndroidJUnitRunner"
+            android:targetPackage="android.annotation.test"/>
+</manifest>
diff --git a/javatests/android/annotation/RestrictedForTests.java b/javatests/android/annotation/RestrictedForTests.java
new file mode 100644
index 0000000..a2b932f
--- /dev/null
+++ b/javatests/android/annotation/RestrictedForTests.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2024 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 android.annotation;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.annotation.RestrictedFor.Environment;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class RestrictedForTests {
+
+    @Test
+    public void testAnnotationAvailableInRuntime() throws Exception {
+        ClassWithAnnotation clz = new ClassWithAnnotation();
+        RestrictedFor annotation = clz.getClass().getAnnotation(RestrictedFor.class);
+
+        assertThat(annotation).isNotNull();
+    }
+
+    @Test
+    public void testAnnotationIsRepeatable() throws Exception {
+        ClassWithRepeatedAnnotation clz = new ClassWithRepeatedAnnotation();
+        RestrictedFor[] annotations = clz.getClass().getAnnotationsByType(RestrictedFor.class);
+
+        assertThat(annotations).hasLength(2);
+    }
+
+    @Test
+    public void testAnnotationParameters() throws Exception {
+        ClassWithAnnotation clz = new ClassWithAnnotation();
+        RestrictedFor annotation = clz.getClass().getAnnotation(RestrictedFor.class);
+
+        Environment[] e = annotation.environments();
+        assertThat(e).asList().containsExactly(Environment.SDK_SANDBOX);
+        int from = annotation.from();
+        assertThat(from).isEqualTo(33);
+    }
+
+    @Test
+    public void testAnnotationParameters_environmentToString() throws Exception {
+        ClassWithAnnotation clz = new ClassWithAnnotation();
+        RestrictedFor annotation = clz.getClass().getAnnotation(RestrictedFor.class);
+
+        Environment e = annotation.environments()[0];
+        assertThat(e).isEqualTo(Environment.SDK_SANDBOX);
+        assertThat(e.toString()).isEqualTo("SDK Runtime");
+    }
+
+    @Test
+    public void testAnnotationParameters_environment_multipleEnvironments() throws Exception {
+        ClassWithMultipleEnvironment clz = new ClassWithMultipleEnvironment();
+        RestrictedFor annotation = clz.getClass().getAnnotation(RestrictedFor.class);
+
+        Environment[] e = annotation.environments();
+        assertThat(e).asList().containsExactly(Environment.SDK_SANDBOX, Environment.SDK_SANDBOX);
+    }
+
+    @RestrictedFor(environments=Environment.SDK_SANDBOX, from=33)
+    private static class ClassWithAnnotation {
+    }
+
+    @RestrictedFor(environments=Environment.SDK_SANDBOX, from=0)
+    @RestrictedFor(environments=Environment.SDK_SANDBOX, from=0)
+    private static class ClassWithRepeatedAnnotation {
+    }
+
+    @RestrictedFor(environments={Environment.SDK_SANDBOX, Environment.SDK_SANDBOX}, from=0)
+    private static class ClassWithMultipleEnvironment {
+    }
+}