The legal/httpcore-niossl-LICENSE.txt file should be deleted.
As of HTTPCore 4.0 beta1 the httpcore-niossl files were merged into the httpcore-nio jar. There is no longer a separate httpcore-niossl jar.
See this note in the httpcomponents-core-4.0-beta1.zip RELEASE_NOTES.txt
- HttpCore NIOSSL classes moved to HttpCore NIO.
Contributed by Oleg Kalnichevski <olegk at apache.org>