Patient.java

package BloodMatch.src.bloodmatch;

import java.io.*;
import java.util.ArrayList;
import java.util.List;

// a class, which manipulates with patients.txt file
public class Patient {
    static List<String> list = new ArrayList<>();
    static String line;

    // method, which adds patients's information to data/requests.txt
    public static void addPatient(String id, String name, String bloodType, String city, int priority) {
        writeRequest(id, name, city, bloodType, priority);

        System.out.println(id + " has been written to " +
                "our database successfully.");
    }

    // method, which reads the file to array.
    public static void readToArray() {
        list.clear();

        try (BufferedReader in = new BufferedReader(new FileReader("BloodMatch\\data\\patients.txt"))) {
            while ((line = in.readLine()) != null) {
                list.add(line);
            }
        } catch (IOException exc) {
            System.out.println("It seems that exception has been ocurred: " + exc);
        }
    }

    // method, which matches the patiens id and city.
    public static boolean matchWithDonor(String id) {
        // check, if patient exists in out database.
        String blood = getBlood(id);
        String city = getCity(id);
        if ((city == null) || (blood == null)) {
            System.out.println("Patient with " + id + " doesn't exist.");
            return false;
        }
        return Donor.matchBlood(id, blood, city);
    }

    // method, which matches the patiens id and city.
    public static String matchForId(String id) {
        // check, if patient exists in out database.
        String blood = getBlood(id);
        String city = getCity(id);
        if (!(blood == null || city == null)) {
            return Donor.matchForId(id, blood, city);
        }
        System.out.println("Irrelevant information for blood and city.");
        return null;
    }

    // method, which returns the city of the patient.
    private static String getCity(String id) {
        readToArray();

        // iterate through arraylist.
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).startsWith("Id: ") && list.get(i).substring(4).equals(id)) {
                return list.get(i + 3).substring(6);
            }
        }
        return null;
    }

    // method, which returns the urgenct of the patiens.
    public static int getUrgency(String id) {
        readToArray();

        // iterate through the list
        for (int i = 0; i < list.size(); i++) {

            // check, if array's id matches the patient's.
            if (list.get(i).startsWith("Id: ") && list.get(i).substring(4).equals(id)) {
                String prior = list.get(i + 4).substring(9);
                return Integer.parseInt(prior);

            }
        }
        return -1;
    }

    // method, which returns the bloodType of the patient.
    private static String getBlood(String id) {
        readToArray();

        // iterate through the list.
        for (int i = 0; i < list.size(); i++) {

            // check, if array's id matches the patient's.
            if (list.get(i).startsWith("Id: ") && list.get(i).substring(4).equals(id)) {
                return list.get(i + 2).substring(11); // return formated bloodtype.
            }
        }
        return null;
    }

    // method, which writes information to the database.
    private static void writeRequest(String id, String name, String bloodType, String city, int priority) {
        try (BufferedWriter out = new BufferedWriter(new FileWriter("BloodMatch\\data\\patients.txt", true))) {
            if (!idExists(id)) {
                out.write("Id: " + id + "\n");
                out.write("Name: " + name + "\n");
                out.write("BloodType: " + bloodType + "\n");
                out.write("City: " + city + "\n");
                out.write("Urgency: " + priority + "\n");
                out.write("---\n");
                return;
            }
        } catch (IOException exc) {
            System.out.println("It seems, exception has been occurred: " + exc);
        }

        System.out.println(id + "already exists in our database!");
    }

    // method, which removes donor from the database.
    public static void removePatient(String id) {
        readToArray();

        // iterate through list.
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).startsWith("Id: ") && list.get(i).substring(4).equals(id)) {
                for (int j = 0; j < 6; j++) {
                    list.remove(i);
                }
                rewritePatient();
                return;
            }
        }
    }

    // method, which rewrites the information of 'requests.txt'.
    private static void rewritePatient() {
        try (BufferedWriter out = new BufferedWriter(new FileWriter("BloodMatch\\data\\patients.txt"))) {
            for (String l : list) {
                out.write(l + "\n");
            }
        } catch (IOException exc) {
            System.out.println("It seems, exception has been occurred: " + exc);
        }

    }

    // method, which checks if donor's id exists.
    private static boolean idExists(String id) {
        try (BufferedReader in = new BufferedReader(new FileReader("BloodMatch\\data\\patients.txt"))) {

            // read to the end of the file.
            while (((line = in.readLine()) != null)) {
                // start comparring id's if line starts with "Id: ".
                if (line.startsWith("Id: ") && line.substring(4).equals(id)) {
                    return true;
                }
            }
        } catch (IOException exc) {
            System.out.println("It seems, exception has been occurred: " + exc);
        }
        return false;
    }
}