From 12b3928ad89d4ecb65c237384bc9f1a5f6cb377a Mon Sep 17 00:00:00 2001
From: Stephen Crawford <steecraw@amazon.com>
Date: Thu, 20 Apr 2023 11:16:00 -0400
Subject: [PATCH] add annotation

Signed-off-by: Stephen Crawford <steecraw@amazon.com>
---
 .../java/org/opensearch/common/NotNull.java   | 32 +++++++++++++++++++
 server/build.gradle                           |  2 ++
 .../opensearch/plugins/IdentityPlugin.java    |  4 +--
 3 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 libs/common/src/main/java/org/opensearch/common/NotNull.java

diff --git a/libs/common/src/main/java/org/opensearch/common/NotNull.java b/libs/common/src/main/java/org/opensearch/common/NotNull.java
new file mode 100644
index 0000000000000..ecbd2851291ae
--- /dev/null
+++ b/libs/common/src/main/java/org/opensearch/common/NotNull.java
@@ -0,0 +1,32 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.common;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import javax.annotation.Nonnull;
+import javax.annotation.meta.TypeQualifierNickname;
+
+/**
+ * The presence of this annotation on a method indicates that
+ * {@code null} will not be returned from that method.
+ *
+ * @opensearch.api
+ */
+@Documented
+@TypeQualifierNickname
+@Nonnull
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.METHOD })
+public @interface NotNull {
+}
+
diff --git a/server/build.gradle b/server/build.gradle
index 2eea312699798..b9e2b88b4532c 100644
--- a/server/build.gradle
+++ b/server/build.gradle
@@ -92,6 +92,8 @@ dependencies {
   api project(':libs:opensearch-secure-sm')
   api project(':libs:opensearch-x-content')
   api project(":libs:opensearch-geo")
+    implementation 'org.jetbrains:annotations:23.0.0'
+  implementation 'org.jetbrains:annotations:23.0.0'
 
   compileOnly project(':libs:opensearch-plugin-classloader')
   testRuntimeOnly project(':libs:opensearch-plugin-classloader')
diff --git a/server/src/main/java/org/opensearch/plugins/IdentityPlugin.java b/server/src/main/java/org/opensearch/plugins/IdentityPlugin.java
index 7246720cba3aa..924d45243faea 100644
--- a/server/src/main/java/org/opensearch/plugins/IdentityPlugin.java
+++ b/server/src/main/java/org/opensearch/plugins/IdentityPlugin.java
@@ -8,7 +8,7 @@
 
 package org.opensearch.plugins;
 
-import org.opensearch.common.Nullable;
+import org.opensearch.common.NotNull;
 import org.opensearch.identity.Subject;
 
 /**
@@ -21,6 +21,6 @@ public interface IdentityPlugin {
     /**
      * Get the current subject
      * */
-    @Nullable
+    @NotNull
     public Subject getSubject();
 }