Blackdown: https://www.blackdown.org/
Sun Microsystems' Java web site:
https://java.sun.com/
NetBeans IDE:
https://www.netbeans.com/
Together/J IDE:
https://www.togetherj.com/
Java Communications API for Linux:
https://www.frii.com/~jarvi/rxtx
The Java Tutorial:
https://java.sun.com/docs/books/tutorial/index.html