Calling Java from VB.NET: Every Option from REST to In-Process Bridging

If you've ever Googled "call Java from VB.NET" and gotten nothing but abandoned StackOverflow threads from 2014, you're not alone. VB.NET is quietly running millions of enterprise apps — financial platforms, healthcare systems, logistics — and those teams increasingly need to tap into Java libraries they can't rewrite. I spent a week mapping out every approach that actually works in 2026. Here's what I found. The Problem: Two Runtimes, No Shared Anything VB.NET runs on the .NET CLR.