Official plugin is available
It seems like the Mojohaus plugin itself is no longer maintained. See https://github.com/mojohaus/jaxws-maven-plugin/issues/54#issuecomment-504335749 for details.
Please try the official Maven plugin from https://github.com/eclipse-ee4j/metro-jax-ws/tree/master/jaxws-ri/jaxws-maven-plugin via
  <dependency>
    <groupId>com.sun.xml.ws</groupId>
    <artifactId>jaxws-maven-plugin</artifactId>
    <version>2.3.2</version>
  </dependency>  
before you use this plugin.
MojoHaus JAX-WS Maven Plugin
This is a fork of the MojoHaus jaxws-maven-plugin. It is based on the 2.6-SNAPSHOT branch from 2018-11-21 including the PR from @theit for Java 9 support.
This is a work around release for Java 9 to 12 compatibility
Please note the changed Maven <groupId> which is now com.helger.maven.
This plugin is meant to work as a direct replacement to org.codehaus.mojo:jaxws-maven-plugin:2.5
News and Noteworthy
- v2.6.2 - 2019-06-25
 - v2.6.1 - 2019-05-07 
  
- Integrated https://github.com/mojohaus/jaxws-maven-plugin/issues/19
 - Added Java 12 support
 
 - v2.6 - 2018-11-21 
  
- Initial release
 
 
Maven usage
<plugin>
  <groupId>com.helger.maven</groupId>
  <artifactId>jaxws-maven-plugin</artifactId>
  <version>2.6.2</version>
  <configuration>
    ...
  </configuration>
</plugin> 
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