Introduce @Discouraged for discouraged APIs
This change adds @Discouraged to the internal annotations library. This
annotation will be used to mark elements that are inadvisable for some
reason, and will be used in lint checks.
Bug: 178477913
Test: Built and flashed successfully
Change-Id: Ie67bd43eb1a2971bfe8b1b29f7d91e45fe3499bf
diff --git a/java/android/annotation/Discouraged.java b/java/android/annotation/Discouraged.java
new file mode 100644
index 0000000..5938a90
--- /dev/null
+++ b/java/android/annotation/Discouraged.java
@@ -0,0 +1,53 @@
+/*
+ * 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 android.annotation;
+
+import static java.lang.annotation.ElementType.CONSTRUCTOR;
+import static java.lang.annotation.ElementType.FIELD;
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.PARAMETER;
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.SOURCE;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+/**
+ * Denotes that the annotated element, while not disallowed or deprecated, is one that
+ * programmers are generally discouraged from using.
+ * <p>
+ * Example:
+ * <pre><code>
+ * @Discouraged(message = "It is much more efficient to retrieve "
+ * + "resources by identifier than by name.")
+ * public void getValue(String name) {
+ * ...
+ * }
+ * </code></pre>
+ * </p>
+ * @hide
+ */
+@Retention(SOURCE)
+@Target({CONSTRUCTOR, FIELD, METHOD, PARAMETER, TYPE})
+public @interface Discouraged {
+ /**
+ * Defines the message to display when an element marked with this annotation is used. An
+ * alternative should be provided in the message.
+ */
+ String message() default "";
+}
+
