How to wrap Method handle behind a class?

[tison]

I'm using OpenJDK 21 and prototyping FFM APIs.

Instead of passing the MethodHandle returned by linker.downcallHandle here
and there, I'm trying to wrap it into a NativeMethod class:

public final class NativeMethod {
    private final String name;
    private final FunctionDescriptor descriptor;
    private final MethodHandle handle;
    public Object invoke(Object... args) throws Throwable {
        return this.handle.invoke(args);
    }
}

But it seems the varargs pass through is not quit fluent:

java.lang.invoke.WrongMethodTypeException: cannot convert
MethodHandle(int)int to (Object[])Object

at
java.base/java.lang.invoke.MethodHandle.asTypeUncached(MethodHandle.java:903)
at java.base/java.lang.invoke.MethodHandle.asType(MethodHandle.java:870)
at java.base/java.lang.invoke.Invokers.checkGenericType(Invokers.java:541)
at io.montumi.datafusion.core.NativeMethod.invoke(NativeMethod.java:22)

While if I public the handle and call invoke from the handle directly, all
the behavior is expected.

Best,
tison.
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