Generate @IntDef annotations for nanoproto enums.

@IntDef is a support library annotation which allows build tools to
determine the valid set of values for a given integer field when that
field is intended to be restricted like an enum. This avoids the
overhead of enums while still allowing for compile-time type checking
in most circumstances.

Change-Id: Iee02e0b49a8e069f6456572f538e0a0d301fdfd5

1 files changed, 23 insertions, 1 deletions

diff --git a/java/README.txt b/java/README.txt
index 7081a84..b02e88b 100644
--- a/java/README.txt
+++ b/java/README.txt
@@ -593,6 +593,28 @@ ignore_services={true,false} (default: false)
 parcelable_messages={true,false} (default: false)
   Android-specific option to generate Parcelable messages.
 
+generate_intdefs={true,false} (default: false)
+  Android-specific option to generate @IntDef annotations for enums.
+
+  If turned on, an @IntDef annotation (a public @interface) will be
+  generated for each enum, and every integer parameter and return
+  value in the generated code meant for this enum will be annotated
+  with it. This interface is generated with the same name and at the
+  same place as the enum members' container interfaces described
+  above under enum_style=java, regardless of the enum_style option
+  used. When this is combined with enum_style=java, the interface
+  will be both the @IntDef annotation and the container of the enum
+  members; otherwise the interface has an empty body.
+
+  Your app must declare a compile-time dependency on the
+  android-support-annotations library.
+
+  For more information on how these @IntDef annotations help with
+  compile-time type safety, see:
+  https://sites.google.com/a/android.com/tools/tech-docs/support-annotations
+  and
+  https://developer.android.com/reference/android/support/annotation/IntDef.html
+
 
 To use nano protobufs within the Android repo:
 
@@ -646,7 +668,7 @@ Please run the following steps to test:
 - "make -j12 aprotoc libprotobuf-java-nano aprotoc-test-nano-params NanoAndroidTest" and
   check for build errors.
 - Plug in an Android device or start an emulator.
-- adb install -r out/target/product/generic/data/app/NanoAndroidTest.apk
+- adb install -r out/target/product/generic/data/app/NanoAndroidTest/NanoAndroidTest.apk
 - Run:
   "adb shell am instrument -w com.google.protobuf.nano.test/android.test.InstrumentationTestRunner"
   and verify all tests pass.