Function Java_com_stateset_embedded_Inventory_nativeReserve 

#[unsafe(no_mangle)]
pub extern "system" fn Java_com_stateset_embedded_Inventory_nativeReserve<'local>(
    env: JNIEnv<'local>,
    _class: JClass<'local>,
    ptr: jlong,
    sku: JString<'local>,
    quantity: jdouble,
)