error: cannot find symbol@javax.annotation.Generated

Java 9: javax.annotation.processing.Generated
Java 8: javax.annotation.Generated

adding a dependency on javax.annotation:javax.annotation-api,or --add-modules java.xml.ws.annotation

dependencies {
    compile group: 'javax.annotation', name: 'javax.annotation-api', version: '1.3.2'
}

If you are using JetBrains IntelliJ IDE, configure dependency. the JDK may cause the problem:

<dependency>
    <groupId>javax.annotation</groupId>
    <artifactId>javax.annotation-api</artifact Id>
    <version>1.2</version>
  </dependency>

or add following line to client/build.gradle:

implementation 'javax.annotation:javax.annotation-api:1.3.2'