From 379e09d157fcb9f4248deb934a80176c8ffb2663 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C3=A5rten=20Kongstad?= <amhk@google.com>
Date: Fri, 8 Sep 2023 15:25:02 +0200
Subject: [PATCH] aconfig: @hide generated Java code

Flagged APIs are annotated using `@FlaggedApi(Flags.FLAG_NAME)`, where
Flags.FLAG_NAME was auto-generated by aconfig.

When metalava generates an API signature file, it can either

  a) insert the value of the constant ("com.foo.bar.flag_name"), or
  b) insert the name of the constant (FLAG.NAME)

In the case of @FlaggedApi, we want a). This requires that

  x) metlava has access to the definition of the constant while generating the API signature file, and
  y) the constant is not part of the API surface of the API signature file

x) is handled by the build system, y) is handled by the aconfig code
generation.

This CL @hide:s all generated Java code, to make sure it is accessible
within the platform, but never part of any API surface.

Bug: 297881670
Test: atest aconfig.test aconfig.test.java
Change-Id: I328ed1a652a4e5e293f2f4b11f916d29fc2fbcbd
---
 tools/aconfig/src/codegen_java.rs                          | 5 +++++
 tools/aconfig/templates/FakeFeatureFlagsImpl.java.template | 1 +
 tools/aconfig/templates/FeatureFlags.java.template         | 1 +
 tools/aconfig/templates/FeatureFlagsImpl.java.template     | 2 ++
 tools/aconfig/templates/Flags.java.template                | 1 +
 5 files changed, 10 insertions(+)

diff --git a/tools/aconfig/src/codegen_java.rs b/tools/aconfig/src/codegen_java.rs
index c31d715867..39b286a13f 100644
--- a/tools/aconfig/src/codegen_java.rs
+++ b/tools/aconfig/src/codegen_java.rs
@@ -118,6 +118,7 @@ mod tests {
 
     const EXPECTED_FEATUREFLAGS_COMMON_CONTENT: &str = r#"
     package com.android.aconfig.test;
+    /** @hide */
     public interface FeatureFlags {
         @com.android.aconfig.annotations.AssumeFalseForR8
         boolean disabledRo();
@@ -132,6 +133,7 @@ mod tests {
 
     const EXPECTED_FLAG_COMMON_CONTENT: &str = r#"
     package com.android.aconfig.test;
+    /** @hide */
     public final class Flags {
         public static final String FLAG_DISABLED_RO = "com.android.aconfig.test.disabled_ro";
         public static final String FLAG_DISABLED_RW = "com.android.aconfig.test.disabled_rw";
@@ -163,6 +165,7 @@ mod tests {
     package com.android.aconfig.test;
     import java.util.HashMap;
     import java.util.Map;
+    /** @hide */
     public class FakeFeatureFlagsImpl implements FeatureFlags {
         public FakeFeatureFlagsImpl() {
             resetAll();
@@ -234,6 +237,7 @@ mod tests {
         let expect_featureflagsimpl_content = r#"
         package com.android.aconfig.test;
         import android.provider.DeviceConfig;
+        /** @hide */
         public final class FeatureFlagsImpl implements FeatureFlags {
             @Override
             public boolean disabledRo() {
@@ -316,6 +320,7 @@ mod tests {
         "#;
         let expect_featureflagsimpl_content = r#"
         package com.android.aconfig.test;
+        /** @hide */
         public final class FeatureFlagsImpl implements FeatureFlags {
             @Override
             public boolean disabledRo() {
diff --git a/tools/aconfig/templates/FakeFeatureFlagsImpl.java.template b/tools/aconfig/templates/FakeFeatureFlagsImpl.java.template
index 82bea81f92..d4283d37a2 100644
--- a/tools/aconfig/templates/FakeFeatureFlagsImpl.java.template
+++ b/tools/aconfig/templates/FakeFeatureFlagsImpl.java.template
@@ -3,6 +3,7 @@ package {package_name};
 import java.util.HashMap;
 import java.util.Map;
 
+/** @hide */
 public class FakeFeatureFlagsImpl implements FeatureFlags \{
     public FakeFeatureFlagsImpl() \{
         resetAll();
diff --git a/tools/aconfig/templates/FeatureFlags.java.template b/tools/aconfig/templates/FeatureFlags.java.template
index 31cfdfce8d..9350d60bec 100644
--- a/tools/aconfig/templates/FeatureFlags.java.template
+++ b/tools/aconfig/templates/FeatureFlags.java.template
@@ -1,5 +1,6 @@
 package {package_name};
 
+/** @hide */
 public interface FeatureFlags \{
 {{ for item in class_elements}}
 {{ -if not item.is_read_write }}
diff --git a/tools/aconfig/templates/FeatureFlagsImpl.java.template b/tools/aconfig/templates/FeatureFlagsImpl.java.template
index 96de06c3e9..1736af94c5 100644
--- a/tools/aconfig/templates/FeatureFlagsImpl.java.template
+++ b/tools/aconfig/templates/FeatureFlagsImpl.java.template
@@ -3,6 +3,7 @@ package {package_name};
 {{ if is_read_write- }}
 import android.provider.DeviceConfig;
 {{ endif }}
+/** @hide */
 public final class FeatureFlagsImpl implements FeatureFlags \{
 {{ for item in class_elements}}
     @Override
@@ -21,6 +22,7 @@ public final class FeatureFlagsImpl implements FeatureFlags \{
 }
 {{ else }}
 {#- Generate only stub if in test mode #}
+/** @hide */
 public final class FeatureFlagsImpl implements FeatureFlags \{
 {{ for item in class_elements}}
     @Override
diff --git a/tools/aconfig/templates/Flags.java.template b/tools/aconfig/templates/Flags.java.template
index 7f047001d2..95a7f3b0fa 100644
--- a/tools/aconfig/templates/Flags.java.template
+++ b/tools/aconfig/templates/Flags.java.template
@@ -1,5 +1,6 @@
 package {package_name};
 
+/** @hide */
 public final class Flags \{
 {{- for item in class_elements}}
     public static final String FLAG_{item.flag_name_constant_suffix} = "{item.device_config_flag}";