Base de datos de ciudades Ejercicio Java - Curso de Programación Java

import java.util.*;
public class Main
{
	private final static class city
	{
		public String name;
		public int inhabitants;

		public city clone()
		{
			city varCopy = new city();

			varCopy.name = this.name;
			varCopy.inhabitants = this.inhabitants;

			return varCopy;
		}
	}

	public static void main(String[] args)
	{
		int maxCities = 500;
		city[] cities = new city[maxCities];
		int amount = 0;
		int currentCityNumber;
		String option;
		String textToSearch;
		boolean found;
		String textToModify;
		boolean finished = false;

		do
		{
			System.out.println();
			System.out.println("Cities database");
			System.out.println();
			System.out.println("1.- Add a new city");
			System.out.println("2.- View all cities");
			System.out.println("3.- Modify a record");
			System.out.println("4.- Insert a new record");
			System.out.println("5.- Delete a record");
			System.out.println("6.- Search in the records");
			System.out.println("7.- Correct the capitalization of the names");
			System.out.println("0.- Exit");
			System.out.println();
			System.out.print("Choose an option: ");
			option = new Scanner(System.in).nextLine();

			switch (option)
			{
				case "0":
					finished = true;
					break;

				case "1":
					if (amount > maxCities - 1)
					{
						System.out.println("the database is full");
					}
					else
					{
						System.out.printf("Entering data for city number %1$s" + "\r\n", amount + 1);
						System.out.print("Enter the city name: ");
						cities[amount].name = new Scanner(System.in).nextLine();
						System.out.print("Enter the inhabitants numbers: ");
						cities[amount].inhabitants = Integer.parseInt(new Scanner(System.in).nextLine());
						System.out.println("The data was entered correctly");
						amount++;
					}
					break;

				case "2":
					for (int i = 0; i < amount; i++)
					{
						System.out.printf("%1$s: %2$s, %3$s inhabitants" + "\r\n", i + 1, cities[i].name, cities[i].inhabitants);
					}
					System.out.println();
					break;

				case "3":
					System.out.print("Enter the city number: ");
					currentCityNumber = Integer.parseInt(new Scanner(System.in).nextLine());
					System.out.printf("Enter a new data for a city number: %1$s" + "\r\n", currentCityNumber);
					System.out.printf("City name (was %1$s; hit ENTER to leave as is): ", cities[currentCityNumber - 1].name);
					textToModify = new Scanner(System.in).nextLine();
					if (!textToModify.equals(""))
					{
						cities[currentCityNumber - 1].name = textToModify;
					}
						System.out.printf("Inhabitants (was %1$s; hit ENTER to leave as is): ", cities[currentCityNumber - 1].inhabitants);
						textToModify = new Scanner(System.in).nextLine();
						if (!textToModify.equals(""))
						{
							cities[currentCityNumber - 1].inhabitants = Integer.parseInt(textToModify);
						}
							System.out.println();
							break;
				case "4":
					if (amount > maxCities - 1)
					{
						System.out.println("The database is full");
					}
					else
					{
						System.out.print("Enter the number of the city to modify: ");
						currentCityNumber = Integer.parseInt(new Scanner(System.in).nextLine());
						System.out.printf("Insert a new data at %1$s position: " + "\r\n",currentCityNumber);
						amount++;
						for (int i = (int)amount; i > currentCityNumber - 1; i--)
						{
							cities[i] = cities[i - 1].clone();
						}
						System.out.print("City name: ");
						cities[currentCityNumber - 1].name = new Scanner(System.in).nextLine();
						System.out.print("Inhabitants: ");
						cities[currentCityNumber - 1].inhabitants = Integer.parseInt(new Scanner(System.in).nextLine());
					}
					break;

				case "5":
					System.out.print("Enter the city number for delete: ");
					currentCityNumber = Integer.parseInt(new Scanner(System.in).nextLine());
					System.out.printf("Deleting the number %1$s" + "\r\n", currentCityNumber);
					for (int i = currentCityNumber - 1; i < amount; i++)
					{
						cities[i] = cities[i + 1].clone();
					}
					amount--;
					break;

				case "6":
					System.out.print("Enter the text to search: ");
					textToSearch = new Scanner(System.in).nextLine();
					found = false;
					for (int i = 0; i < amount; i++)
					{
						if (cities[i].name.toUpperCase().indexOf(textToSearch.toUpperCase()) >= 0)
						{
							System.out.printf("%1$s found in %2$s" + "\r\n", textToSearch, cities[i].name);
							found = true;
						}
					}
					if (!found)
					{
						System.out.println("Not found.");
					}
						break;

				case "7":
					for (int i = 0;i < amount;i++)
					{
						String lowerCaseName = cities[i].name.toLowerCase();
						String correctedName = lowerCaseName.substring(0, 1).toUpperCase() + lowerCaseName.substring(1);
						for (int j = 1; j < correctedName.length() - 2; j++)
						{
							if (correctedName.charAt(j) == ' ')
							{
							correctedName = correctedName.substring(0, j) + " " + correctedName.substring(j + 1, j + 1 + 1).toUpperCase() + correctedName.substring(j + 2);
							}
						}
						cities[i].name = correctedName;
					}
					break;

				default:
					System.out.println("Wrong option ");
					break;
			}

		} while (!finished);
	}
}