Java Setters not working as intended on Array object

Question

I´m quite new to Java and want to write code that creates objects, shows (prints) and edits them.

I wrote a class:

public class Person {

protected String firstName;
protected String lastName;
protected String fullName;
protected Date dob;
protected int id;

public Person(String firstName, String lastName, Date dob, int id) {
    this.firstName = firstName;
    this.lastName = lastName;
    this.dob = dob;
    this.fullName = this.firstName + " " + this.lastName;
    this.id = id;

}

public String getFirstName() {return this.firstName;}
public String getLastName() {return this.lastName;}
public String getFullName() {
    return this.fullName;
}
public Date getDob() {
    return this.dob;
}
public int getId() {
    return this.id;
}

public void printAll() {
    System.out.println(this.fullName);
    System.out.println(this.dob);
    System.out.println(this.id);
}

public void setFirstName(String firstName) {
    this.firstName = firstName;
}

public void setLastName(String lastName) {
    this.lastName = lastName;
}

public void setDob(Date dob) {
    this.dob = dob;
}

public boolean containsFullName(String fullName) {
    if (this.fullName.equalsIgnoreCase(fullName)) {
        return true;
    } else {
        return false;
    }
}
public boolean containsId(int id) {
    if (this.id == id) {
        return true;
    } else {
        return false;
    }
}

}

I created an Array of Person in Main Class. (100 objects).

public class Main {

final static int MAX_NUMBER_PERSONS = 100;
static Person[] person = new Person[MAX_NUMBER_PERSONS];
static int mainCount = 0;
static Scanner scan = new Scanner(System.in);

upon corresponding command the user may create an object within this array (It´s german, but basically its reading first name, last name and date of birth). mainCount is used to keep track on which position within the array the object is created:

public static void createPerson() throws ParseException {

Scanner scan = new Scanner(System.in);

// Namen erfassen:
System.out.println("Bitte den Vornamen der Person eingeben:");
String firstName = scan.nextLine();
System.out.println("Bitte den Nachnamen der Person eingeben:");
String lastName = scan.nextLine();
String fullName = firstName + " " + lastName;

// DOB erfassen:
System.out.println("Bitte Geburtsdatum von " + fullName + " eingeben (TT/MM/JJJJ):");
String dob = scan.next();
Date dobDate = new SimpleDateFormat("dd/MM/yyyy").parse(dob);

int id = mainCount;

person[mainCount] = new Person(firstName, lastName, dobDate, id);
++mainCount;
System.out.println("Du hast Person Nummer " + mainCount + " erstellt");

}

NOW THE ACTUAL ISSUE: calling the following method the user should be able to edit the desired object within the array by using user input and setters:

public static void editPerson() throws ParseException { Scanner scan = new Scanner(System.in); System.out.println("Bitte die ID der zu bearbeitenden Person eingeben (zu finden über )..."); int id = scan.nextInt(); scan.nextLine(); searchByIdReturn(id).printAll();

System.out.println("Diese Person bearbeiten? Tippe <ja>, sonst zurück zum Menü.");
if(scan.next().equalsIgnoreCase("ja")) {
    scan.nextLine();
    System.out.println("Vorname eingeben...");
    String firstName = scan.nextLine();
    searchByIdReturn(id).setFirstName(firstName);
    System.out.println("Nachname eingeben...");
    String lastName = scan.nextLine();
    searchByIdReturn(id).setLastName(lastName);
    System.out.println("Bitte Geburtsdatum eingeben (TT/MM/JJJJ):");
    String dob = scan.next();
    Date dobDate = new SimpleDateFormat("dd/MM/yyyy").parse(dob);
    searchByIdReturn(id).setDob(dobDate);
}

}

After the Method I look up the object. First and last name remain unchanged. dob however is was changed as required.

What am I missing?

Thank you so much in andvance!

What are the values you provided? What does searchById returns? How do you say that date was changed? — Gibbs
By the way, the terrible Date class was supplanted years ago by java.time classes. For your purpose, use LocalDate. — Basil Bourque

Peter Lawrey Peter Lawrey · Accepted Answer · 2020-05-14T12:45:46

You never change the fullName which is what I assume you are looking at.

this.fullName = this.firstName + " " + this.lastName;

You don't need to store it, it would be simpler to calculate it each time.

public String getFullName() {
    return this.firstName + " " + this.lastName;
}

BTW tests are boolean already so you an write.

public boolean containsId(int id) {
    return this.id == id;
}

Java Setters not working as intended on Array object

1 Answers