Do you have a Java assignment where your lecturer prevents you from using a modern database to handle your data?
Are you FORCED to use crude .txt files as your data storage method?
TextORM is an Object–relational mapping framework that works with .txt files!
No longer would you have to wrestle with file opening and line splitting and re-writing whole files just to get your data saved and read.
Querying data is as easy as
Vaccine sinovac = TextORM.getOne(Vaccine.class, dataMap -> Objects.equals(dataMap.get("vaccineName"), "Sinovac"));And saving data is as easy as
new Vaccine("Sinovac", 21, 120.00, false).save();All-in-one example
public class Main {
public static void main(String[] args) {
Vaccine sinovac = new Vaccine("Sinovac", 21, 120.00, false);
sinovac.setdaysBetweenDoses(14);
sinovac.save();
List<Vaccine> finishedVaccines = TextORM.getAll(Vaccine.class, dataMap -> Boolean.parseBoolean(dataMap.get("isFinished")));
for (Vaccine vaccine : finishedVaccines) {
vaccine.delete();
}
}
}Here is an example model
@Repository
public class Vaccine extends Model {
@Column
private String vaccineName;
@Column
private int daysBetweenDoses;
@Column
private double cost;
@Column
private boolean isFinished = false;
public Vaccine(String vaccineName, int daysBetweenDoses, double cost, boolean isFinished) {
this.cost = cost;
this.vaccineName = vaccineName;
this.daysBetweenDoses = daysBetweenDoses;
this.isFinished = isFinished;
}
public Vaccine() {
}
/* getters and setters... */
}Inheritance works as you'd expect. View example below.
in Person.java
@Repository
public class Person extends Model {
@Column
private String name;
@Column
private int age;
@Column
private double balance;
@Column
private LocalDate birthDate;
public Person(String name, int age, double balance, LocalDate birthDate) {
this.name = name;
this.age = age;
this.balance = balance;
this.birthDate = birthDate;
}
public Person() {
}
/* setters and getters... */
}in Account.java
@Repository
public class Account extends Person {
@Column
private String username;
@Column
private String password;
@Column
private int vaccineCenterId;
public Account(String name, int age, double balance, LocalDate birthDate, String username, String password) {
super(name, age, balance, birthDate);
this.username = username;
this.password = password;
}
public Account(String username, String password) {
this.username = username;
this.password = password;
}
public Account() {
}
/* getters and setters... */
}TextORM also supports lazy loading of related models. See below.
in VaccineCenter.java
@Repository
public class VaccineCenter extends Model {
@Column
private String name;
@Column
private Double longitude;
@Column
private Double latitude;
@Column
private int vaccineId;
@HasOne(foreignKey = "vaccineId")
private Vaccine vaccine;
@HasMany(targetKey = "vaccineCenterId")
private List<Account> assignedAccounts;
public VaccineCenter(String name, Double longitude, Double latitude) {
this.name = name;
this.longitude = longitude;
this.latitude = latitude;
}
public VaccineCenter() {
}
/* getters and setters... */
}in Main.java
public class Main {
public static void main(String[] args) {
VaccineCenter movenpick = TextORM.getOne(VaccineCenter.class, dataMap -> Objects.equals(dataMap.get("name"), "Movenpick"));
if (movenpick != null) {
movenpick.include(Vaccine.class);
System.out.printf("The vaccine at %s is %s and costs RM %,.2f. Is finished: %b", movenpick.getName(), movenpick.getVaccine().getVaccineName(), movenpick.getVaccine().getCost(), movenpick.getVaccine().isFinished());
movenpick.getVaccine().setCost(Math.round(100.0 * (500.0 * Math.random())) / 100.0);
// Saving the parent model also saves the included models.
movenpick.save();
}
}
}To use eager loading in TextORM, simply list down the models you wish to include when using getOne() or getAll(). See below.
in Main.java
public class Main {
public static void main(String[] args) {
VaccineCenter movenpick = TextORM.getOne(VaccineCenter.class, dataMap -> Objects.equals(dataMap.get("name"), "Movenpick"), Vaccine.class /* <- Here */);
if (movenpick != null) {
System.out.printf("The vaccine at %s is %s and costs RM %,.2f. Is finished: %b", movenpick.getName(), movenpick.getVaccine().getVaccineName(), movenpick.getVaccine().getCost(), movenpick.getVaccine().isFinished());
movenpick.getVaccine().setCost(Math.round(100.0 * (500.0 * Math.random())) / 100.0);
// Saving the parent model also saves the included models.
movenpick.save();
}
}
}To use one-to-many relationship in your models, A field of type Array must be annotated with @HasMany(targetKey = "key")
where "key" is the name of the foreign key in the included model which points to the including model. See below.
in VaccineCenter.java
@Repository
public class VaccineCenter extends Model {
@Column
private String name;
@Column
private Double longitude;
@Column
private Double latitude;
@Column
private int vaccineId;
@HasOne(foreignKey = "vaccineId")
private Vaccine vaccine;
@HasMany(targetKey = "vaccineCenterId") /* <- Here */
private List<Account> assignedAccounts;
public VaccineCenter(String name, Double longitude, Double latitude) {
this.name = name;
this.longitude = longitude;
this.latitude = latitude;
}
public VaccineCenter() {
}
/* getters and setters... */
}in Account.java
@Repository
public class Account extends Person {
@Column
private String username;
@Column
private String password;
// targetKey = "vaccineCenterId"
// is referring to this field here.
@Column
private int vaccineCenterId;
public Account(String name, int age, double balance, LocalDate birthDate, String username, String password) {
super(name, age, balance, birthDate);
this.username = username;
this.password = password;
}
public Account(String username, String password) {
this.username = username;
this.password = password;
}
public Account() {
}
/* getters and setters... */
}Then, including it is as usual, through eager or lazy loading. Both works. See below.
in Main.java
public class Main {
public static void main(String[] args) {
VaccineCenter jalil = TextORM.getOne(VaccineCenter.class, dataMap -> Objects.equals(dataMap.get("name"), "Bukit Jalil Stadium"), Vaccine.class, Account.class);
if (jalil != null) {
System.out.printf("The vaccine at %s is %s and costs RM %,.2f. Is finished: %b%n", jalil.getName(), jalil.getVaccine().getVaccineName(), jalil.getVaccine().getCost(), jalil.getVaccine().isFinished());
for (Account account : jalil.getAssignedAccounts()) {
System.out.println(account.getName());
}
// Example of adding a new model
// Account pakAbu = new Account("Pak Abu", 63, 400.00, LocalDate.of(1967, 4, 23), PersonRace.MALAY, "pakabu113", "123qwe", jalil.getId());
// jalil.getAssignedAccounts().add(pakAbu);
// Saving the parent model also saves all included models.
jalil.save();
}
}
}