FFM (Foreign Function and Memory) Stdlib Example
FFM is the new API trying to replace JNI and jep is here It is basically calling functions outside of JVM or accessing memory not managed by JVM. I wanted to test can FFM beat regular Java API, below you can find a simple test doing math sin with FFM and with regular Math.sin import java.lang.foreign.FunctionDescriptor; import java.lang.foreign.Linker; import java.lang.foreign.MemorySegment; import java.lang.foreign.SymbolLookup; import java.lang.foreign.ValueLayout; public class FFMSinTest { public static void main(String[] args) throws Throwable { Linker linker = Linker.nativeLinker(); SymbolLookup stdlib = linker.defaultLookup(); // Locate the "sin" function in the C math library MemorySegment sinAddress = stdlib.find("sin").orElseThrow(); FunctionDescriptor descriptor = FunctionDescriptor.of(ValueLayout.JAVA_DOUBLE, ValueLayout.JAVA_DOUBLE); var sinHandle = linker.downcallHandle(sinAddress, descriptor); double angle = Math.PI / 4; // 45 degrees in radians // Timing Java's Math.sin() long javaStartTime = System.nanoTime(); for (int i = 0; i < 1_000_000; i++) { double result = Math.sin(angle); } long javaEndTime = System.nanoTime(); long javaDuration = javaEndTime - javaStartTime; // Timing C sin via FFM long ffmStartTime = System.nanoTime(); for (int i = 0; i < 1_000_000; i++) { double result = (double) sinHandle.invoke(angle); } long ffmEndTime = System.nanoTime(); long ffmDuration = ffmEndTime - ffmStartTime; System.out.println("Java Math.sin() took: " + javaDuration / 1_000_000.0 + " ms"); System.out.println("C sin (FFM) took: " + ffmDuration / 1_000_000.0 + " ms"); } } And result is ...