Paradigms are not strictly disjoint and the paradigm landscape is richer and more varied than many people expect. For example, Java's OO paradigm is very different to, say, Python's, and Excel's expression of functional programming is very different to Haskell's. There is a lot of variety and range!
So to add to Trisha's "It depends" we need to understand that Java has a number of features that better support OO than FP. It is unlikely Java will ever be a functional programming language and there is a lot in the existing language that works against functional programming. For example, by default Java is imperative in how it treats its data. Changing such a default is like changing the laws of physics. It would break everything, and for minimal value. Java also doesn't support functions! This is the most basic construct in functional programming, but Java only permits classes and interfaces as top-level constructs.
Certainly, Java can be programmed in a way that is influenced by FP, and Java 8+ makes this easier. Adding lambdas and streams brings Java closer to FP, but neither streams nor lambdas are specific and unique to FP. If you look at blocks and collection pipelines in languages such as Smalltalk and Ruby, it looks more like Java is becoming more OO!