JNIKit
It is a foundation library that provides best in class Swift layer for Java Native Interface with automatic memory management, convenient methods to work with Java objects, beautiful wrappers for Java types, and more.
Yeah nah it's not swift-java, it's an alternative foundation provided by the Swift Stream Family.
Installation
Open your Package.swift and add the following dependency:
// package dependencies
.package(url: "https://github.com/swifdroid/jni-kit.git", from: "2.10.0")
// target dependencies
.product(name: "JNIKit", package: "jni-kit")
Then head to the → basics