Add support for Java

[pgosar]

What is the name of this language in Linguist?

Java

Link to GitHub repository of Vim plugin

https://github.com/uiiaoo/java-syntax.vim

Is this plugin well maintained?

Technically it is not maintained, but it is very stable so there is no need to

Is this plugin lightweight? (no advanced functionality, just indent and syntax support)

yes, all it does is provide syntax support