kpt-grpc-demo/google/type/README.md

Google Common Types

This package contains definitions of common types for Google APIs. All types defined in this package are suitable for different APIs to exchange data, and will never break binary compatibility. They should have design quality comparable to major programming languages like Java and C#.

NOTE: Some common types are defined in the package google.protobuf as they are directly supported by Protocol Buffers compiler and runtime. Those types are called Well-Known Types.

Java Utilities

A set of Java utilities for the Common Types are provided in the //java/com/google/type/util/ package.