Comment by pjmlp

Java IDEs have historically been made by maintainers of the language.

Netbeans was a product acquired by Sun, Sun Forte was its "Professional" variant in Solaris, and Oracle still takes care of it in the context of Solaris and Oracle Linux.

Eclipse was a rewrite from Visual Age products, originall written in Smalltalk, by IBM, and IBM keeps being a Java vendor with their own implementations.