private IConsole console;
public void onStart(IContext context) throws JFException {
this.console = context.getConsole();
}

public void onTick(Instrument instrument, ITick tick) throws JFException {
console.getOut().println("Instrument:" + instrument + " ask price:" + tick.getAsk());
}

Code print nothing...

Most likely you are trying to invoke onTick method in Market Offline hours.

Thanks ,I will try it.

But yesterday I used the same code to print log, it still printed nothing...

It's impossible to identify problem only by few line of code. Please, provide full your strategy sample.

for tick.getBid/Ask you have to imply history - example: history.getLastTick(Instrument.EURUSD).getAsk()

import com.dukascopy.api.IHistory;

////on class //
this.history = context.getHistory();

That's the examples in Jforex,console didn't print the instrument......

package examples;

import java.util.*;
import java.text.*;

import com.dukascopy.api.*;

public class BollingerBandExample implements IStrategy {
    private IEngine engine;
    private IConsole console;
    private IHistory history;
    private IContext context;
    private IIndicators indicators;
    private IUserInterface userInterface;

    @Configurable("selectedInstrument:")
    public Instrument selectedInstrument = Instrument.EURUSD;
    @Configurable("selectedPeriod:")
    public Period selectedPeriod = Period.TEN_MINS;
    @Configurable("stopLossPips:")
    public int stopLossPips = 25;
    @Configurable("takeProfitPips:")
    public int takeProfitPips = 50;

    private boolean lowCross = false;
    private boolean upperCross = false;

    private static final DateFormat DATE_FORMAT = new SimpleDateFormat("yyyyMMdd_HHmmss");

    public void onStart(IContext context) throws JFException {
        this.engine = context.getEngine();
        this.console = context.getConsole();
        this.history = context.getHistory();
        this.context = context;
        this.indicators = context.getIndicators();
        this.userInterface = context.getUserInterface();

        context.setSubscribedInstruments(Collections.singleton(selectedInstrument), true);
    }

    public void onAccount(IAccount account) throws JFException {
    }

    public void onMessage(IMessage message) throws JFException {
    }

    public void onStop() throws JFException {
    }

    public void onTick(Instrument instrument, ITick tick) throws JFException {
    }

    public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws JFException {
        if (!instrument.equals(selectedInstrument) || !period.equals(selectedPeriod)) {
            return;
        }
    

    console.getOut().println("Instrument:" + selectedInstrument);

        long time = bidBar.getTime();
        Object[] indicatorResult = indicators.calculateIndicator(selectedInstrument, selectedPeriod, new OfferSide[] {OfferSide.BID},
                "BBANDS", new IIndicators.AppliedPrice[] {IIndicators.AppliedPrice.CLOSE}, new Object[] {20, 2.0, 2.0, 0}, Filter.WEEKENDS, 1, time, 0);
        double bollingerUpperValue = ((double[]) indicatorResult[0])[0];
        double bollingerMiddleValue = ((double[]) indicatorResult[1])[0];
        double bollingerLowerValue = ((double[]) indicatorResult[2])[0];

        if (askBar.getClose() < bollingerLowerValue) {
            lowCross = true;
        }
        if (bidBar.getClose() > bollingerUpperValue) {
            upperCross = true;
        }

        if (lowCross && askBar.getClose() >= bollingerLowerValue) {
            boolean existLong = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existLong = order.isLong();
                    if (existLong) {
                        break;
                    }
                }
            }

            if (!existLong) {
                double stopLoss = bidBar.getClose() - selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = bidBar.getClose() + selectedInstrument.getPipValue() * takeProfitPips;

                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.BUY, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }

            upperCross = false;
            lowCross = false;

        } else if (upperCross && bidBar.getClose() <= bollingerUpperValue) {
            boolean existShort = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existShort = !order.isLong();
                    if (existShort) {
                        break;
                    }
                }
            }

            if (!existShort) {
                double stopLoss = askBar.getClose() + selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = askBar.getClose() - selectedInstrument.getPipValue() * takeProfitPips;

                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.SELL, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }

            upperCross = false;
            lowCross = false;
        }
    }

    private String getLabel(long time) {
        return "IVF" + DATE_FORMAT.format(time) + generateRandom(10000) + generateRandom(10000);
    }

    private String generateRandom(int n) {
        int randomNumber = (int) (Math.random() * n);
        String answer = "" + randomNumber;
        if (answer.length() > 3) {
            answer = answer.substring(0, 4);
        }
        return answer;
    }
}

I have already used IHistory.

There you Go !
Moved printing line to onTick(Instrument instrument, ITick tick)
I did not work because you call ITick tick onBar
((( public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws ….)))

 
import java.util.*;
import java.text.*;
 
import com.dukascopy.api.*;
 
public class BollingerBandExample implements IStrategy {
    private IEngine engine;
    private IConsole console;
    private IHistory history;
    private IContext context;
    private IIndicators indicators;
    private IUserInterface userInterface;
 
    @Configurable("selectedInstrument:")
    public Instrument selectedInstrument = Instrument.EURUSD;
    @Configurable("selectedPeriod:")
    public Period selectedPeriod = Period.TEN_MINS;
    @Configurable("stopLossPips:")
    public int stopLossPips = 25;
    @Configurable("takeProfitPips:")
    public int takeProfitPips = 50;
 
    private boolean lowCross = false;
    private boolean upperCross = false;
 
    private static final DateFormat DATE_FORMAT = new SimpleDateFormat("yyyyMMdd_HHmmss");
 
    public void onStart(IContext context) throws JFException {
        this.engine = context.getEngine();
        this.console = context.getConsole();
        this.setHistory(context.getHistory());
        this.setContext(context);
        this.indicators = context.getIndicators();
        this.setUserInterface(context.getUserInterface());
 
        context.setSubscribedInstruments(Collections.singleton(selectedInstrument), true);
    }
 
    public void onAccount(IAccount account) throws JFException {
    }
 
    public void onMessage(IMessage message) throws JFException {
    }
 
    public void onStop() throws JFException {
    }
 
    public void onTick(Instrument instrument, ITick tick) throws JFException {
      console.getOut().println("Instrument:" + instrument + " ask price:" + tick.getAsk());
    }
 
    public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws JFException {
        if (!instrument.equals(selectedInstrument) || !period.equals(selectedPeriod)) {
            return;
        }


        long time = bidBar.getTime();
        Object[] indicatorResult = indicators.calculateIndicator(selectedInstrument, selectedPeriod, new OfferSide[] {OfferSide.BID},
                "BBANDS", new IIndicators.AppliedPrice[] {IIndicators.AppliedPrice.CLOSE}, new Object[] {20, 2.0, 2.0, 0}, Filter.WEEKENDS, 1, time, 0);
        double bollingerUpperValue = ((double[]) indicatorResult[0])[0];
        @SuppressWarnings("unused")
      double bollingerMiddleValue = ((double[]) indicatorResult[1])[0];
        double bollingerLowerValue = ((double[]) indicatorResult[2])[0];
 
        if (askBar.getClose() < bollingerLowerValue) {
            lowCross = true;
        }
        if (bidBar.getClose() > bollingerUpperValue) {
            upperCross = true;
        }
 
        if (lowCross && askBar.getClose() >= bollingerLowerValue) {
            boolean existLong = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existLong = order.isLong();
                    if (existLong) {
                        break;
                    }
                }
            }
 
            if (!existLong) {
                double stopLoss = bidBar.getClose() - selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = bidBar.getClose() + selectedInstrument.getPipValue() * takeProfitPips;
 
                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.BUY, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }
 
            upperCross = false;
            lowCross = false;
 
        } else if (upperCross && bidBar.getClose() <= bollingerUpperValue) {
            boolean existShort = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existShort = !order.isLong();
                    if (existShort) {
                        break;
                    }
                }
            }
 
            if (!existShort) {
                double stopLoss = askBar.getClose() + selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = askBar.getClose() - selectedInstrument.getPipValue() * takeProfitPips;
 
                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.SELL, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }
 
            upperCross = false;
            lowCross = false;
        }
    }
 
    private String getLabel(long time) {
        return "IVF" + DATE_FORMAT.format(time) + generateRandom(10000) + generateRandom(10000);
    }
 
    private String generateRandom(int n) {
        int randomNumber = (int) (Math.random() * n);
        String answer = "" + randomNumber;
        if (answer.length() > 3) {
            answer = answer.substring(0, 4);
        }
        return answer;
    }

   public IHistory getHistory() {
      return history;
   }

   public void setHistory(IHistory history) {
      this.history = history;
   }

   public IContext getContext() {
      return context;
   }

   public void setContext(IContext context) {
      this.context = context;
   }

   public IUserInterface getUserInterface() {
      return userInterface;
   }

   public void setUserInterface(IUserInterface userInterface) {
      this.userInterface = userInterface;
   }
}

Method 2 - calling IHistory onBar

public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws JFException {
console.getOut().println("Instrument:" + instrument + " ask price:" + history.getLastTick(instrument).getAsk());

 
import java.util.*;
import java.text.*;
 
import com.dukascopy.api.*;
 
public class BollingerBandExample implements IStrategy {
    private IEngine engine;
    private IConsole console;
    private IHistory history;
    private IContext context;
    private IIndicators indicators;
    private IUserInterface userInterface;
 
    @Configurable("selectedInstrument:")
    public Instrument selectedInstrument = Instrument.EURUSD;
    @Configurable("selectedPeriod:")
    public Period selectedPeriod = Period.TEN_MINS;
    @Configurable("stopLossPips:")
    public int stopLossPips = 25;
    @Configurable("takeProfitPips:")
    public int takeProfitPips = 50;
 
    private boolean lowCross = false;
    private boolean upperCross = false;
 
    private static final DateFormat DATE_FORMAT = new SimpleDateFormat("yyyyMMdd_HHmmss");
 
    public void onStart(IContext context) throws JFException {
        this.engine = context.getEngine();
        this.console = context.getConsole();
        this.setHistory(context.getHistory());
        this.setContext(context);
        this.indicators = context.getIndicators();
        this.setUserInterface(context.getUserInterface());
 
        context.setSubscribedInstruments(Collections.singleton(selectedInstrument), true);
    }
 
    public void onAccount(IAccount account) throws JFException {
    }
 
    public void onMessage(IMessage message) throws JFException {
    }
 
    public void onStop() throws JFException {
    }
 
    public void onTick(Instrument instrument, ITick tick) throws JFException {
    }
 
    public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws JFException {
          console.getOut().println("Instrument:" + instrument + " ask price:" + history.getLastTick(instrument).getAsk());

       if (!instrument.equals(selectedInstrument) || !period.equals(selectedPeriod)) {
            return;
        }


        long time = bidBar.getTime();
        Object[] indicatorResult = indicators.calculateIndicator(selectedInstrument, selectedPeriod, new OfferSide[] {OfferSide.BID},
                "BBANDS", new IIndicators.AppliedPrice[] {IIndicators.AppliedPrice.CLOSE}, new Object[] {20, 2.0, 2.0, 0}, Filter.WEEKENDS, 1, time, 0);
        double bollingerUpperValue = ((double[]) indicatorResult[0])[0];
        @SuppressWarnings("unused")
      double bollingerMiddleValue = ((double[]) indicatorResult[1])[0];
        double bollingerLowerValue = ((double[]) indicatorResult[2])[0];
 
        if (askBar.getClose() < bollingerLowerValue) {
            lowCross = true;
        }
        if (bidBar.getClose() > bollingerUpperValue) {
            upperCross = true;
        }
 
        if (lowCross && askBar.getClose() >= bollingerLowerValue) {
            boolean existLong = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existLong = order.isLong();
                    if (existLong) {
                        break;
                    }
                }
            }
 
            if (!existLong) {
                double stopLoss = bidBar.getClose() - selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = bidBar.getClose() + selectedInstrument.getPipValue() * takeProfitPips;
 
                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.BUY, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }
 
            upperCross = false;
            lowCross = false;
 
        } else if (upperCross && bidBar.getClose() <= bollingerUpperValue) {
            boolean existShort = false;
            for (IOrder order : engine.getOrders(selectedInstrument)) {
                if (order.getState() == IOrder.State.OPENED || order.getState() == IOrder.State.FILLED) {
                    existShort = !order.isLong();
                    if (existShort) {
                        break;
                    }
                }
            }
 
            if (!existShort) {
                double stopLoss = askBar.getClose() + selectedInstrument.getPipValue() * stopLossPips;
                double takeProfit = askBar.getClose() - selectedInstrument.getPipValue() * takeProfitPips;
 
                engine.submitOrder(getLabel(time), selectedInstrument, IEngine.OrderCommand.SELL, 0.1, 0, 5, stopLoss, takeProfit, 0, "");
            }
 
            upperCross = false;
            lowCross = false;
        }
    }
 
    private String getLabel(long time) {
        return "IVF" + DATE_FORMAT.format(time) + generateRandom(10000) + generateRandom(10000);
    }
 
    private String generateRandom(int n) {
        int randomNumber = (int) (Math.random() * n);
        String answer = "" + randomNumber;
        if (answer.length() > 3) {
            answer = answer.substring(0, 4);
        }
        return answer;
    }

   public IHistory getHistory() {
      return history;
   }

   public void setHistory(IHistory history) {
      this.history = history;
   }

   public IContext getContext() {
      return context;
   }

   public void setContext(IContext context) {
      this.context = context;
   }

   public IUserInterface getUserInterface() {
      return userInterface;
   }

   public void setUserInterface(IUserInterface userInterface) {
      this.userInterface = userInterface;
   }
}

Do you think console.getout() can't work in OnBar()?

Method 2 - calling IHistory onBar

public void onBar(Instrument instrument, Period period, IBar askBar, IBar bidBar) throws JFException {
console.getOut().println("Instrument:" + instrument + " ask price:" + history.getLastTick(instrument).getAsk());


Please run the tests I gave you before you make statements ….. I answer your questions and I gave you examples …..

Cheers

Thanks for your help,but unfortunately, consle still print nothing.
Console.getout() is a methond that call by user, but user can't see how it was encapsulated，So I need the developer's help.
I don't think it have difference between OnBar() or OnTick().

console.getOut() method in your strategy example works correctly.
Note that onBar executes only on fully formed candles.

Does it work well in BackTest?

Yes, of course. But in HT you need select "Show messages" checkbox

But my console didn't print anything...

Very strange. Take a screenshot and upload it here.

https://drive.google.com/open?id=11DZfF ... FgdxmYkvMv

Please help.

You talked about problem with console in backtesting, or not? In this case messages will be printed in "Historical Tester" tab.