Where is javax.annotation

The dependency including version:

<dependency>
    <groupId>javax.annotation</groupId>
    <artifactId>javax.annotation-api</artifactId>
    <version>1.3.2</version>
</dependency>

See: http://mvnrepository.com/artifact/javax.annotation/javax.annotation-api

Or for the newer jakarta.annotation:

<dependency>
   <groupId>jakarta.annotation</groupId>
   <artifactId>jakarta.annotation-api</artifactId>
   <version>1.3.5</version>
</dependency>

See: https://mvnrepository.com/artifact/jakarta.annotation/jakarta.annotation-api

The Java Common Annotations Module java.xml.ws.annotation was deprecated in Java version 9 and was removed in java version 11. If this leads to a problem you could try to add javax.annotation.

The Javadocs for Java 8 can be found here:
http://docs.oracle.com/javase/8/docs/api/javax/annotation/package-summary.html