BUILDING.md

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# Building

Apache Ratis uses Apache Maven 3.3.9 or later to build the artifacts.
You can use the bundled Maven Wrapper to build without a pre-installed Maven,
by replacing `mvn` with the `mvnw` (*nix) or `mvnw.cmd` (Windows) script in the root path.

Apache Ratis is written in Java 8.
Therefore, it as well requires Java 8 or later.

Project could be built as a usual Maven project:

```
$ mvn clean package -DskipTests
```

Note: subsequent builds could be faster with skiping shading/protobuf compile steps.
See the next section for more info.

# Thirdparty

All bundled thirdparty dependencies are centralized in the *ratis-thirdparty* module
and the *ratis-thirdparty-misc* module.
These modules are located in a separated repository
but not attached to the core Apache Ratis repository
as they only need to change when one of these dependencies are changed.
All dependencies included in ratis-thirdparty/ratis-thirdparty-misc
must be relocated to a different package to ensure no downstream classpath pollution.

Ratis developers should rely on these relocated thirdparty classes.

As a result of this thirdparty module, there is no need for `skipShade` options in the
build which previously existed because the shaded artifacts that are generated each
build are limited only to the code in Ratis itself.

## What packages are shaded?

| Original packages                   | Shaded packages                                                  |
| ------------------------------------|------------------------------------------------------------------|
| `com.google.common`                 | `org.apache.ratis.thirdparty.com.google.common`                  |
| `com.google.protobuf`               | `org.apache.ratis.thirdparty.com.google.protobuf`                |
| `com.google.thirdparty.publicsuffix`| `org.apache.ratis.thirdparty.com.google.thirdparty.publicsuffix` |
| `io.grpc`                           | `org.apache.ratis.thirdparty.io.grpc`                            |
| `io.netty`                          | `org.apache.ratis.thirdparty.io.netty`                           |

All compiled protocol-buffer definitions in `ratis-proto` are stored in the
`org.apache.ratis.proto` Java package.