private ObjectAssert<Object> assertFlags(String flagsMethod) throws Throwable {
        final Lookup lookup = MethodHandles.publicLookup();
        Class<?> rtype = Flags.class.getMethod(flagsMethod).getReturnType();
        if (!rtype.isPrimitive()) {
            rtype = flagsClassLoader.loadClass(rtype.getCanonicalName());
        }
        final MethodHandle method =
                lookup.findStatic(flags, flagsMethod, MethodType.methodType(rtype));
        return assertThat(method.invoke());
    }
Makes sure OpenSSL SSLEngine is used instead of JDK SSLEngine while running tests
on Linux, Windows and OS X.
core/src/test/java/com/linecorp/armeria/common/FlagsTest.java