can i Develop an iOS app in Java

While I'm sure more that more than one dev has included JAVA in their toolbox, Apple's IDE is tied to macOS.

There is no publicly supported or approved Java compiler or interpreter for iOS.

If there were, I can't imagine what it could use for its interface library, since Swing would be terrible on a mobile device, AWT is a non-starter, and there's a lot of work that would be needed to produce a HIG compliant intermediate layer.

So unless the scope of your project starts with "Port Java to iOS, then start developing application", the answer is "No".