Thread: dateOfBirth problems

Hi, I am doing an assignment that requires me to input a Person with the usual params - name, gender, address, insurance number and date of birth.

I have managed all but dateOfBirth. I will post the code here. My spec:

dateOfBirth should be class Date NB: I have another class created called Date. I don't know how to do this

my constructors spec is like this:

constructors
Person() //after this has run, dateOfBirth, name, address, natInscNo != null; and counter incremented

Person(String nme, char sex, Date dob, String insceNumber)
// // //
before this is run dob != null
after this is run instance variables initialised with params. address != null; counter incremented

my code for class person, if you need the code for Date or Controller please ask:

 
public class Person
{
    // instance variables
    protected String name;
    protected char gender;
    protected Date dateOfBirth;
    protected String address;
    protected String natInsceNo;
 
    private static int counter;
 
    public static int count()
    {
        return counter;
    }
 
    /**
     * Constructor for objects of class Person
     */
    public Person(String nme, char sex, Date dob, String insceNumber)
    {
        // initialise instance variables
        name = nme;
        dateOfBirth = new Date(dob);
        getGender(sex);
        address = "";
        natInsceNo = insceNumber;
        counter = 0;
        counter++;
    }
 
    public Person()
    {
        name = "";
        address = "";
        natInsceNo = "";
        counter++;
    }
 
    public void setName(String nme)
    {
        name = nme;
    }
 
    public String getName()
    {
        return name;
    }
 
    public void setAddress(String addr)
    {
        address = addr;
    }
 
    public String getAddress()
    {
        return address;
    }
 
    public void setdateOfBirth(Date dob)
    {
        dateOfBirth = dob;
    }
 
    public Date getdateOfBirth(Date dob)
    {
        return dateOfBirth;
    }
 
    public void getGender(char sex)
    {
        gender = sex;        
    }
 
    public void getnatInsceNo(String insceNumber)
    {
        natInsceNo = insceNumber;
    }
 
    public String toString()
    {
        return "Name: " + name + " DOB: " + dateOfBirth + " Gender: " + gender + 
        " Address: " + address + " NatIns No: " + natInsceNo;
    }
 
    public void copy(Person other)
    {
        //creates another instance of Person
        name = other.name;
        gender = other.gender;
        dateOfBirth = other.dateOfBirth;
        natInsceNo = other.natInsceNo;
    }    
 
    public boolean equals(Person other)
    {
        //returns true if the name and national insurance number 
        //are the same as the values in other.
        return name.equals(other.name) && natInsceNo.equals(other.natInsceNo);
    }
}

One more thing is, I am using blueJ, and part of my spec is to create a person in there by right clicking on the class person, clicking Person() and then once that is created, I have to set the name, dob etc. then clicking getdateOfBirth() should return the date of birth. But when I type the date of birth in to the box, it says:

incompatible types, found int but expected date. What do I have to enter to get it as a date? I know strings use "" and chars use ''

Date is mostly deprecated. Calendar works better.

However, wouldn't a String work best?

October 9, 1920

10/09/1920

Hey, yeah it would. But my spec specifies that dateOfBirth should be type Date. I have also just found out that in the controller I need to get the user to input a date of birth, but there isn't a getDate like there is getString or getInt. Any ideas for any of these problems?

 
static final int JANUARY= 0;
static final int FEBRUARY = 1;
static final int MARCH = 2;
static final int APRIL = 3;
static final int MAY = 4;
static final int JUNE = 5;
static final int JULY = 6;
static final int AUGUST = 7;
static final int SEPTEMBER = 8;
static final int OCTOBER = 9;
static final int NOVEMBER = 10;
static final int DECEMBER = 11;
private int year;
private int month;
private int date;
public Date(int year,
            int month,
            int date)
{
year = this.year;
month = this.month;
setMonth(month);
date = this.date;
}
 
public void setMonth(int month2)
{
month = month2;
}
 
public String getMonth()
{
if (month == Date.JANUARY)
return "January";
else if (month == Date.FEBRUARY)
return "February";
else if (month == Date.MARCH)
return "March";
else if (month == Date.APRIL)
return "April";
 
etc
 
}

Also, you'll need a sex and this.sex in and before your constructor in order for the code below to work:

public Person copy()
{
Person p = new Person(this.name, this.sex, this.dateOfBirth, this. natInsceNo);
return p;
}

Also, why isn't the address passed as parameter to constructor? Just curious.

I will try that code, although I am not totally sure if I am allowed to add more instance variables.

And I tried the code with the this.sex code and it brought back cannot find variable sex

public Date(int year, int month, int date)
    {
        year = this.year;
        month = this.month;
        setMonth(month);
        date = this.date;
    }

brings the error message:

invalid method declaration; return type required

Originally Posted by ibby50

public Date(int year, int month, int date)
    {
        year = this.year;
        month = this.month;
        setMonth(month);
        date = this.date;
    }

brings the error message:

invalid method declaration; return type required

That's supposed to be the constructor for the Date class.

sorry, nothing is supposed to inherit from the date class. I am supposed to set the date of birth as a date type in person depending on what the user inputs and then get the integers again as a string

Data type?

Make DOB an object of Date?

Have a method getDateOfBirth and setDateOfBirth.

I think that's what they want you to do.

I don't get

nothing is supposed to inherit from the Date class

Well...I did think of something.

Do you have to pass the DOB as a parameter to person?

Couldn't you just have a method
Date d;
setDateOfBirth(int month, int day, int year)
{
d = new Date(month, day, year);
}

or something like that.

Does your Date class have a getDateOfBirth() method?

If so, it can call that to get Date of Birth.

However, I'm not sure how to pass it as parameter to Person class, the Date object that is.

dateOfBirth = new Date(dob);

There is no constructor in Date with one parameter so that line above will make an error.

You'll have to pass it as a parameter with int month, int day, int year in the Person class.

then
dateOfBirth = new Date(month, day,year);

All your getMethods should have no parameters usually.

The only time you'd probably have a parameter is if your get method was both setting something and then returning a value.

You do nothing with the parameter dob.

public boolean equals(Date other)
{
//returns true if the day, month and year values are the same as the values in other.
return day == other.day && month == other.month && year == other.year;
}

The method is supposed to return a boolean.

If the getDay() and getMonth() and getYear() values of the Date in the parameter are all equal to the getDay() and getMonth() and getYear of the current data object(this), then it's true
otherwise false

it doesn't. But I am not sure I can add more methods either to Date. Oh well.

I did find one thing. In the spec, it says my dateOfBirth instance variable should be class Date

does that change anything? because that makes me think that they're trying to trick me and I actually AM allowed to extend Date. Although I did ask my tutor and he said that day month and year should all be private.

public Date(Date other)
{
day = other.day;
month = other.month;
year = other.year;
}
You don't have a method name so it assumes that this thing is a constructor.

Also, you don't have setMonth(int month), setDay(int day), setYear(int year) methods.

As I've said before, for the copy,

create a new Date object and pass it like this.year, this.month, this.day, as parameters.

then return that object.

It will create and return a new Date object that won't change when you update the original date values.

Does the date of birth have to be passed as a parameter?

If not, you can just do this:

// note, this is an example

private Date dateOfBirth;

public Person(.......)
{
dateOfBirth = new Date(1,2,3);
}

You just have to pass it the parameters yourself in the constructor.

or you could do this:

private Date dateOfBirth;
public Person(....., int day, int month, int year)
{
......
dateOfBirth = new Date(day, month, year);
}

the first one I tried and I got an error when I entered the date in BlueJ when creating the person. I entered it like 12,12,12

that right?

the second one it gave me an error in the new copy code I used from earlier on.

what do I do with the dob thing? get rid?

Oh, I think I might see why it won't just let you pass it as a parameter.

You do need the day, month, and year as parameters for the Person parameters in order to initialize the dateofbirth object.

No, I guess you don't have to have the dateofbirth as a parameter.

ok done that, now its saying an error in Person copy()

cannot find symbol constructor Person(java.lang.String,char,java.lang.String)

You don't have a constructor (String value, char value2, String value3) do you?

Oh you might.

Let's see the copy method.

In fact, show all the code.

Ok, this is Date:

public class Date
{
    // instance variables
    private int day, month, year;
 
    /**
     * Constructor for objects of class Date
     */
    public Date(int dd, int mm, int yy)
    {
        // initialise instance variables
        day = dd;
        month = mm;
        year = yy;
    }
 
    public Date()
    {
        //sets the default value of day, month and year to 0
        day = month = year = 0;
    }
 
    public int getDay()
    {
        return day;
    }
 
    public int getMonth()
    {
        return month;
    }
 
    public int getYear()
    {
        return year;
    }
 
    public String monthAsString()
    {
        //returns month as a string rather than an integer
        switch (month)
        {
            case 1: return "January";
            case 2: return "February";
            case 3: return "March";
            case 4: return "April";
            case 5: return "May";
            case 6: return "June";
            case 7: return "July";
            case 8: return "August";
            case 9: return "September";
            case 10: return "October";
            case 11: return "November";
            case 12: return "December";
            default: return "";          
        }         
    }
 
    public String toString()
    {
        return day + "/" + month + "/" + year;
    }
 
 
 
    public boolean equals(Date other)
    {
        //returns true if the day, month and year values are the same as the values in other.
        return day == other.day && month == other.month && year == other.year;
    }
 
    public Date(Date other)
    {
        day = other.day;
        month = other.month;
        year = other.year;
    }   
}

This is Person:

public class Person
{
    // instance variables
    protected String name;
    protected char gender;
    protected Date dateOfBirth;
    protected String address;
    protected String natInsceNo;
 
    private static int counter;
 
    /**
     * Constructor for objects of class Person
     */
    public Person()
    {
        name = "";
        address = "";
        natInsceNo = "";
        counter++;
    }
 
    public Person(String nme, char sex, int day, int month, int year, String insceNumber)
    {
        // initialise instance variables
        name = nme;
        dateOfBirth = new Date(day, month, year);
        setGender(sex);
        address = "";
        natInsceNo = insceNumber;
        counter = 0;
        counter++;
    }
 
    public static int count()
    {
        return counter;
    }
 
    public void setName(String nme)
    {
        name = nme;
    }
 
    public String getName()
    {
        return name;
    }
 
    public void setAddress(String addr)
    {
        address = addr;
    }
 
    public String getAddress()
    {
        return address;
    }
 
    public void setdateOfBirth(int day, int month, int year)
    {
        dateOfBirth = new Date(day, month, year);
    }
 
    public Date getdateOfBirth()
    {
        return dateOfBirth;
    }
 
    public void setGender(char sex)
    {
        gender = sex;        
    }
 
    public char getGender()
    {
        return gender;
    }
 
    public void setnatInsceNo(String insceNumber)
    {
        natInsceNo = insceNumber;
    }
 
    public String getnatInsceNo()
    {
        return natInsceNo;
    }
 
    public String toString()
    {
        return "Name: " + name + " DOB: " + dateOfBirth + " Gender: " + gender + 
        " Address: " + address + " NatIns No: " + natInsceNo;
    }
 
   public Person copy()
   {
       Person p = new Person(this.name, this.gender, this.natInsceNo);
       return p;
    }
 
    public boolean equals(Person other)
    {
        //returns true if the name and national insurance number 
        //are the same as the values in other.
        return name.equals(other.name) && natInsceNo.equals(other.natInsceNo);
    }
}

First of all, how are you initializing the Date object dateofbirth?

use this.getName,

or whatever.

Like if you had soemthing that had a constructor

String name, int value, char c;

copy = new classname (this.name, this.value, this.getGender());

or something like that.

i'm sorry I don't understand that

Ahhhh...I see now.

Use dob.getDay(), dob.getYear(), dob.getMonth() for the other ones.

where abouts do i put them? in the Person copy?

In the person copy, yes.

That will copy all the stuff that's current but it won't change if you change the original.