create new object in arraylist with attributes

Question

I am new to Java and I am starting to work with ArrayLists. What I am trying to do is create an ArrayList for students. Each student has different attribute associated with them (name, id). I am trying to figure out how to add a new student object with this attributes. Here is what I have:

ArrayList < Student > studentArray;
public Student(String name, int id) {
  this.fname = name;
  this.stId = id;
}
public Stromg getName() {
  return fname;
}
public int getId() {
  return stId;
}
public boolean setName(String name) {
  this.fname = name;
  return true;
}
public boolean setIdNum(int id) {
  this.stId = id;
  return true;
}

How do I create a new object (Student) with a name and id associated with it that the user inputs? — bardockyo
– bardockyo, Commented Mar 13, 2013 at 4:52
I presume Stromg means String, or this wouldn't compile (unless you actually had a Stromg class lurking around). — Makoto
– Makoto, Commented Mar 13, 2013 at 5:19

Roney Michael · Accepted Answer · 2013-03-13 05:08:10Z

6

What you need is something like the following:

import java.util.*;

class TestStudent
{
    public static void main(String args[])
    {
        List<Student> StudentList= new ArrayList<Student>();
        Student tempStudent = new Student();
        tempStudent.setName("Rey");
        tempStudent.setIdNum(619);
        StudentList.add(tempStudent);
        System.out.println(StudentList.get(0).getName()+", "+StudentList.get(0).getId());
    }
}

class Student
{
    private String fname;
    private int stId;

    public String getName()
    {
        return this.fname;
    }

    public int getId()
    {
        return this.stId;
    }

    public boolean setName(String name)
    {
        this.fname = name;
        return true;
    }

    public boolean setIdNum(int id)
    {
        this.stId = id;
        return true;
    }
}

answered Mar 13, 2013 at 5:08

Roney Michael

3,9945 gold badges32 silver badges45 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Makoto · Accepted Answer · 2013-03-13 04:57:26Z

2

You instantiate a Student object by passing the appropriate values to the constructor.

Student s = new Student("Mr. Big", 31);

You place elements into an ArrayList (or List) by using the .add() operator.^*

List<Student> studentList = new ArrayList<Student>();
studentList.add(s);

You retrieve user input via the use of a Scanner bound to System.in.

Scanner scan = new Scanner(System.in);
System.out.println("What is the student's name?");
String name = scan.nextLine();
System.out.println("What is their ID?");
int id = scan.nextInt();

You repeat this with a loop. That portion shall be left as an exercise to the reader.

^{*: There are other options, but add() simply adds it to the end, which is typically what you want.}

answered Mar 13, 2013 at 4:57

Makoto

107k29 gold badges199 silver badges236 bronze badges

4 Comments

bardockyo Over a year ago

Thank you for the response. I get exactly what you are saying but what purpose are my get/set methods serving in my project if I put the values in like you say?

Makoto Over a year ago

Accessors and mutators. You do want to access the value of their name and their ID, but do you really need to change them? It may be worth removing the setters on those.

Abdullah Shaikh Over a year ago

@bardockyo The values are not yet in Student object you need to put them using setters

Makoto Over a year ago

@AbdullahShaikh: No; considering the way that the object is constructed, it would be impossible for a value to not be in Student (unless null and -1 were passed, and even then those are still values).

Sudhanshu Umalkar · Accepted Answer · 2013-03-13 04:52:52Z

1

final List<Student> students = new ArrayList<Student>();
students.add(new Student("Somename", 1));

... and so on add more students

answered Mar 13, 2013 at 4:52

Sudhanshu Umalkar

4,2021 gold badge26 silver badges33 bronze badges

Collectives™ on Stack Overflow

create new object in arraylist with attributes

3 Answers 3

Comments

4 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related