So the code used to print something all the time and than it stopped.
It does not print "init" nor "calculate" no matter if it's attached to the chart or not.

I press compile. It informs that it compiled ok. Then i go to Workspace >custome indicators > (right click) Risk control > attach to active chart.
Still nothing happens.

package jforex;

import com.dukascopy.api.indicators.*;
import com.dukascopy.api.drawings.*;
import com.dukascopy.api.feed.*;
import com.dukascopy.api.*;
import java.awt.Color;
import java.io.*;

public class RiskControl implements IIndicator {
    private IndicatorInfo indicatorInfo;
    private InputParameterInfo[] inputParameterInfos;
    private OptInputParameterInfo[] optInputParameterInfos;
    private OutputParameterInfo[] outputParameterInfos;
    private double[][] inputs = new double[1][];
    private int timePeriod = 2;
    private double[][] outputs = new double[1][];
    private IIndicatorContext context;
    private IPriceMarkerChartObject slMarker;
    private IPriceMarkerChartObject tpMarker;
    private IPriceMarkerChartObject opMarker;
    private IFeedDescriptor feedDescriptor;
    
    public void onStart(IIndicatorContext context) {
        indicatorInfo = new IndicatorInfo("Risk Control", "", "",
            true, false, false, 1, 1, 1);
        
        inputParameterInfos = new InputParameterInfo[] {new InputParameterInfo("Input data", InputParameterInfo.Type.DOUBLE)};
        
        optInputParameterInfos = new OptInputParameterInfo[] {new OptInputParameterInfo("Time period", OptInputParameterInfo.Type.OTHER,
            new IntegerRangeDescription(2, 2, 100, 1))};
        
        outputParameterInfos = new OutputParameterInfo[] {new OutputParameterInfo("out", OutputParameterInfo.Type.DOUBLE,
            OutputParameterInfo.DrawingStyle.LINE)};
        
        this.context = context;     
        PrintStream stream = context.getConsole().getOut();
        stream.print("init");
    }

    public IndicatorResult calculate(int startIndex, int endIndex) {
        context.getConsole().getOut().print("calculate");

        Draw();

        if (startIndex - getLookback() < 0) {
            startIndex -= startIndex - getLookback();
        }
        int i, j;
        for (i = startIndex, j = 0; i <= endIndex; i++, j++) {
            double value = 0;
            for (int k = timePeriod; k > 0; k--) {
                value += inputs[0][i - k];
            }
            outputs[0][j] = value;
        }
        return new IndicatorResult(startIndex, j);
        
        //return new IndicatorResult(startIndex, 0);
    }
    
    private void Draw(){
        IHistory history = context.getHistory();
        
        IIndicatorChartPanel panel = context.getIndicatorChartPanel();
        if(panel == null){
            context.getConsole().getWarn().print("Panel is null");        
            return;    
        }
        
        IChartObjectFactory factory = panel.getChartObjectFactory();
      
        double balance = context.getAccount().getBalance();
     
        feedDescriptor = context.getFeedDescriptor();
        if(feedDescriptor == null){
            context.getConsole().getWarn().print("Feed descriptor is null");        
            return;    
        }
        Period period = feedDescriptor.getPeriod();        
        Instrument instrument = feedDescriptor.getInstrument();
        if(instrument == null){
            context.getConsole().getWarn().print("Instrument is null");        
            return;
        }
  
        double priceMid;
        try{
            double priceAsk = history.getBar(instrument, period, OfferSide.ASK, 0).getClose();
            double priceBid = history.getBar(instrument, period, OfferSide.BID, 0).getClose();
            priceMid = (priceAsk + priceBid)/2.0;
             context.getConsole().getOut().print("03");
        
        } catch(Exception ex){
            context.getConsole().getWarn().print("Get bar error");        
        
            context.getConsole().getErr().print(ex.toString());
            return;
        }
            
        slMarker = factory.createPriceMarker("SL", priceMid - 20.0 * instrument.getPipValue());
        opMarker = factory.createPriceMarker("OP", priceMid);
        slMarker.setColor(Color.RED);
        opMarker.setColor(Color.ORANGE);
        slMarker.setLineWidth(2.0f);
        opMarker.setLineWidth(2.0f);
            
        context.getConsole().getOut().print("01");
        
        context.getConsole().getOut().print(slMarker.getPrice(0));
        context.getConsole().getOut().print(opMarker.getPrice(0));
     
    }

    public IndicatorInfo getIndicatorInfo() {
        return indicatorInfo;
    }

    public InputParameterInfo getInputParameterInfo(int index) {
        if (index <= inputParameterInfos.length) {
            return inputParameterInfos[index];
        }
        return null;
    }

    public int getLookback() {
        return timePeriod;
    }

    public int getLookforward() {
        return 0;
    }

    public OptInputParameterInfo getOptInputParameterInfo(int index) {
        if (index < optInputParameterInfos.length) {
            return optInputParameterInfos[index];
        }
        return null;
    }

    public OutputParameterInfo getOutputParameterInfo(int index) {
        if (index < outputParameterInfos.length) {
            return outputParameterInfos[index];
        }
        return null;
    }

    public void setInputParameter(int index, Object array) {
        inputs[index] = (double[]) array;
    }

    public void setOptInputParameter(int index, Object value) {
        timePeriod = (Integer) value;
    }

    public void setOutputParameter(int index, Object array) {
        outputs[index] = (double[]) array;
    }
}

Messages will be printed only when newline character is received.
Therefore please replace print with println.