Program That Implements Hash Maps Using Java Programming Language Assignment Solution

Instructions

Objective

Write a java assignment program to implement hash maps using programming language.

Requirements and Specifications

Source Code

package reports; import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.text.MessageFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.*; public class ReportsMain { private static final String INPUT_FOLDER = "Resources"; private static final String OUTPUT_FOLDER = "Reports"; private static final String INPUT_FILENAME = "TimeDataMedium"; private static final String CLIENT_OUTPUT_PREFIX = "Client"; private static final String EMPLOYEE_OUTPUT_PREFIX = "Employee"; public static void main(String[] args) { Map employees = new HashMap<>(); Map> clients = new HashMap<>(); try (Scanner scanner = new Scanner(new File(INPUT_FOLDER + "/" + INPUT_FILENAME + ".csv"))) { scanner.nextLine(); while (scanner.hasNextLine()) { String line = scanner.nextLine().trim(); String[] parts = line.split(","); String employee = parts[0].trim(); String info = parts[1].trim(); String client = parts[3].trim(); if (!client.isEmpty()) { Set singleEmployee = new HashSet<>(); singleEmployee.add(employee); clients.merge(client, singleEmployee, (a, b) -> { a.addAll(b); return a; }); } if (info.equals("Clock In/Out")) { long minutes = getMinutes(parts[4], parts[5], parts[6], parts[7]); employees.merge(employee, minutes, Long::sum); } } } catch (IOException e) { throw new RuntimeException(e); } printClientReport(clients); printEmployeeReport(employees); } private static void printClientReport(Map> clients) { try (PrintWriter writer = new PrintWriter(OUTPUT_FOLDER + "/" + CLIENT_OUTPUT_PREFIX + INPUT_FILENAME + ".txt")) { List clientList = new ArrayList<>(clients.keySet()); Collections.sort(clientList); for (String client : clientList) { List employees = new ArrayList<>(clients.get(client)); Collections.sort(employees); writer.write(MessageFormat.format("CLIENT: {0} --- EMPLOYEES: [{1}]" + System.lineSeparator(), client, String.join(", ", employees))); } } catch (IOException e) { throw new RuntimeException(e); } } private static void printEmployeeReport(Map employees) { try (PrintWriter writer = new PrintWriter(OUTPUT_FOLDER + "/" + EMPLOYEE_OUTPUT_PREFIX + INPUT_FILENAME + ".txt")) { List employeeList = new ArrayList<>(employees.keySet()); Collections.sort(employeeList); for (String employee : employeeList) { Long minutes = employees.get(employee); int hours = (int)(minutes/60); int mins = (int)(minutes%60); String formatted = String.format("%02d:%02d", hours, mins); writer.write(MessageFormat.format("EMPLOYEE: {0} --- TIME: {1}" + System.lineSeparator(), employee, formatted)); } } catch (IOException e) { throw new RuntimeException(e); } } private static long getMinutes(String startTime, String endTime, String startDate, String endDate) { SimpleDateFormat format = new SimpleDateFormat("hh:mm a dd/MM/yyyy"); Date start = null; Date end = null; try { start = format.parse(startTime + " " + startDate); end = format.parse(endTime + " " + endDate); } catch (ParseException e) { e.printStackTrace(); return 0; } long diff = end.getTime() - start.getTime(); return diff / (60 * 1000); } }