If you need to call Java from a .NET app, the first answer is usually “just shell out to java.exe .” That works right up until you need objects, exceptions, throughput, or a deployment story that doesn’t become a pile of scripts. This Dev.to version walks through five practical ways to run Java from C# — from Process.Start to IKVM, JNI, gRPC, and in-process bridging — with code and the tradeoffs that matter in production. TL;DR — Need to run Java from C# ? Use Process.Start for one-off JAR executions, IKVM for pure-Java libraries with no native dependencies, gRPC for microservice architectures, JNI if you have C++ expertise and need raw speed, or JNBridgePro for production-grade in-process bridging with low latency and zero JNI glue code. See the comparison table and decision tree below. You have a Java library you need to use from a C#/.NET application — maybe a payment SDK, a machine-learning model, or a legacy system nobody wants to rewrite.…