manual/core/shaded_jar/README.md

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## Using the shaded JAR

The default `java-driver-core` JAR depends on a number of [third party
libraries](../integration/#driver-dependencies). This can create conflicts if your application
already uses other versions of those same dependencies.

To avoid this, we provide an alternative core artifact that shades [Netty](../integration/#netty),
[Jackson](../integration/#jackson) and [ESRI](../integration/#esri). To use it, replace the
dependency to `java-driver-core` by:

```xml
<dependency>
  <groupId>org.apache.cassandra</groupId>
  <artifactId>java-driver-core-shaded</artifactId>
  <version>${driver.version}</version>
</dependency>
```

If you also use the query-builder, mapper or some other library that depends on java-driver-core,
you need to remove its dependency to the non-shaded JAR:

```xml
<dependency>
  <groupId>org.apache.cassandra</groupId>
  <artifactId>java-driver-core-shaded</artifactId>
  <version>${driver.version}</version>
</dependency>

<dependency>
  <groupId>org.apache.cassandra</groupId>
  <artifactId>java-driver-query-builder</artifactId>
  <version>${driver.version}</version>
  <exclusions>
    <exclusion>
      <groupId>org.apache.cassandra</groupId>
      <artifactId>java-driver-core</artifactId>
    </exclusion>
  </exclusions>
</dependency>
```

Notes:

* the shading process works by moving the libraries under a different package name, and bundling
  them directly into the driver JAR. This should be transparent for client applications: the
  impacted dependencies are purely internal, their types are not surfaced in the driver's public
  API.
* the driver is compatible with all Netty versions in the range `[4.1.7, 4.2.0)` (equal to or higher
  than 4.1.7, and lesser than 4.2.0). If you just need a specific version in that range, you can 
  avoid the need for the shaded JAR by declaring an explicit dependency in your POM:
  
    ```xml
    <dependency>
      <groupId>org.apache.cassandra</groupId>
      <artifactId>java-driver-core</artifactId>
      <version>${driver.version}</version>
    </dependency>
  
    <dependency>
      <groupId>io.netty</groupId>
      <artifactId>netty-handler</artifactId>
      <version>4.1.39.Final</version>
    </dependency>
    ```
  
    This only works with Netty: for Jackson and ESRI, only the exact version declared in the driver POM
    is supported.