Caution
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The java-driver-mapper-processor artifact contains the annotation processor. It hooks into the
Java compiler, and generates additional source files from your annotated classes before the main
compilation happens. It is only required in the compile classpath.
The java-driver-mapper-runtime artifact contains the annotations and a few utility classes. It is
a regular dependency, required at runtime.
The best approach is to add the annotationProcessorPaths option to the compiler plugin’s
configuration (make sure you use version 3.5 or higher):
<properties>
<java-driver.version>...</java-driver.version>
</properties>
<dependencies>
<dependency>
<groupId>com.scylladb</groupId>
<artifactId>java-driver-mapper-runtime</artifactId>
<version>${java-driver.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>1.8</source> <!-- (or higher) -->
<target>1.8</target> <!-- (or higher) -->
<annotationProcessorPaths>
<path>
<groupId>com.scylladb</groupId>
<artifactId>java-driver-mapper-processor</artifactId>
<version>${java-driver.version}</version>
</path>
<!-- Optional: add this if you want to avoid the SLF4J warning "Failed to load class
StaticLoggerBinder, defaulting to no-operation implementation" when compiling. -->
<path>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-nop</artifactId>
<version>1.7.26</version>
</path>
</annotationProcessorPaths>
</configuration>
</plugin>
</plugins>
</build>
Alternatively (e.g. if you are using the BOM), you may also declare the processor as a regular dependency in the “provided” scope:
<dependencies>
<dependency>
<groupId>com.scylladb</groupId>
<artifactId>java-driver-mapper-processor</artifactId>
<version>${java-driver.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.scylladb</groupId>
<artifactId>java-driver-mapper-runtime</artifactId>
<version>${java-driver.version}</version>
</dependency>
</dependencies>
The processor runs every time you execute the mvn compile phase. It normally supports incremental
builds, but if something looks off you can try a full rebuild with mvn clean compile.
One of the advantages of annotation processing is that the generated code is produced as regular
source files, that you can read and debug like the rest of your application. With the above
configuration, these files are in target/generated-sources/annotations. Make sure that
directory is marked as a source folder in your IDE (for example, in IntelliJ IDEA, this might
require right-clicking on your pom.xml and selecting “Maven > Reimport”).
Generated sources follow the same package structure as your annotated types. Most end in a special
__MapperGenerated suffix, in order to clearly identify them in stack traces (one exception is the
mapper builder, because it is referenced directly from your code).
Do not edit those files files directly: your changes would be overwritten during the next full rebuild.
Use the following configuration (Gradle 4.6 and above):
apply plugin: 'java'
def javaDriverVersion = '...'
dependencies {
annotationProcessor group: 'com.scylladb', name: 'java-driver-mapper-processor', version: javaDriverVersion
compile group: 'com.scylladb', name: 'java-driver-mapper-runtime', version: javaDriverVersion
}
You will find the generated files in build/generated/sources/annotationProcessor.