Access .net DLL from Java -


i new java , dll-s

i need access dll's methods java. go easy on me.

i have tried using jna access dll here have done.

import com.sun.jna.library;  public class mapper {    public interface mtapi extends library {         public boolean isstopped();   }    public static void main(string []args){      mtapi lib = (mtapi) native.loadlibrary("mtapi", mtapi.class);      boolean test = lib.isstopped();      system.out.println(test);    } }

when run code, getting following error:

exception in thread "main" java.lang.unsatisfiedlinkerror:
error looking function 'isstopped':
the specified procedure not found.

i understand error saying cannot find function, have no idea how fix it.

i trying use api mt4api

and here method, attempting access mql4

can tell me doing wrong?

i have looked @ other alternatives, jni4net, cannot working either.

if can link me tutorial shows me how set up, or knows how to, greatfull.

trading?
hunting milliseconds shave-off?
go rather distributed processing... safer relying on api !

while op directed onto how bend java call .net dll-functions, let me sketch future-safer solution.

using ai/ml-regression based predictors forex trading, hunting in same forest. best solution found within last 12-years, having spent few hundreds man*years of experience, setup in following manner:

host a executes trades: operates metatrader terminal 4, both script , ea --- distributed-processing system communicates with use of zeromq low-latency messaging/signalling framework ( few tens of microseconds needed )

host b executes ai/ml processing of predictions traded instrument ( few hundreds of microseconds apply )

cluster c executes continuous ai/ml predictor re-trainings , hyperparameterspace model selections ( many cpu-hours indeed needed, continuous model self-adapting process running 24/7 )

signalling / messaging layer zeromq has ports and/or bindings available , ready of mainstream , many of niche programming languages, including java.

hidden dangers of going against published api:

while efforts system integration , testing immense, api specifications dangerous specification creeping.

this said, add countless man*months consumed on debugging after silent change in mt4 language specifications de-rail previous tools + libraries. why? imagine. time ago, mql4 stopped mql4 , silently shifted towards mql5, under name new-mql4. among other changes in compilation, there many small , big nails in coffin -- string surprisingly ceased string , hidden internal struct -- 1 guess cause dll-calls.

so, beware of api creepings.

does hurt distributed processing solution?

no.

with wise message-layout design, there no adverse effects of metatrader terminal 4 behaviour , logic ( incl. strategy decision ) put outside creeping platform.

doable. fast , smart. use remote-gpu-cluster processing, if budget allows.

does work in strategy tester?

yes, does.

if has gut rely on in-built strategy tester, distributed-processing model still works there. performance depends on preferred style of modelling, full 1 year, tick-by-tick simulation, quite complex ai/ml components took few days on common cots desktops pc-systems ( after years of quant r&d, not use strategy tester internally @ all, request batch-test y/y tick-data, commented here ).


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