source: MotivateDuringTherapy/src/main/java/tudelft/mentalhealth/motivatepersisting/MeanNrStatements.java

package tudelft.mentalhealth.motivatepersisting;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/**
 * Table 3: Mean nr. of statements in a given answer per situation, defined by
 * PCL score and Trust. This is a singleton as we have only 1 fixed table
 * backing this, to avoid repeated loading of the table.
 */
public class MeanNrStatements {

        private Map<Situation, Double> meanNrStatements = new HashMap<>();
        private static MeanNrStatements instance;

        private MeanNrStatements() {
                readTable();
        }

        /**
         * @return the whole table, immutable
         */
        public Map<Situation, Double> getTable() {
                return Collections.unmodifiableMap(meanNrStatements);
        }

        /**
         * @return the instance of the MeanNrStatements.
         * @throws IOException
         */
        public static MeanNrStatements instance() {
                if (instance == null) {
                        instance = new MeanNrStatements();
                }
                return instance;
        }

        @Override
        public String toString() {
                return meanNrStatements.toString();
        }

        /**
         * 
         * @param situation the {@link Situation} of the patient.
         * @return the average (mean) number of statements in the situation
         */
        public Double getMean(Situation situation) {
                return meanNrStatements.get(situation);
        }

        private void readTable() {
                InputStream is = MeanNrStatements.class
                                .getResourceAsStream("MeanNrStatements.csv");

                BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                reader.lines().forEach(line -> addLine(line));

        }

        private void addLine(String line) {
                String[] values = line.split(",");
                PclTrend pcl = PclTrend.valueOf(values[0]);
                Trust trust = Trust.valueOf(values[1]);
                Double mean = Double.valueOf(values[2]);
                meanNrStatements.put(new Situation(pcl, trust), mean);
        }
}