I am fairly new to Java and am having some difficulty with implementing an arraylist.

I have some classes that contain variables and i have a new class that contains my arraylist. I would like to know how i would get the variables from the other classes into the arraylist in the new class. I know that you would use the add methods, but am unsure of the code to do it.

Example code would be very useful.

Thanks

Member Avatar for iamthwee

You should just be able to add custom objects into your arrayList as you would say strings etc.

Hi,
if i have got your problem write....this can be the solution.

I have 2 classes A and B and I am adding its variable to arraylist in third class. Take care of access modifiers. Also objects can be added to arraylist like wrapper, string or custom objects along with primitive variables.
<----Array List class----->
import java.util.ArrayList;

publicclass arraylisttest {

public static void main(String[] args) {
ArrayList al = new ArrayList();
A a = new A();
B b = new B();
al.add(A.i);
al.add(B.d);
al.add(A.ii);

}

}

<----Class A---->
publicclass A{
public int ii;
public Integer i;
}

<-----Class B----->
publicclass B{

public Double d;
}

I am fairly new to Java and am having some difficulty with implementing an arraylist.

I have some classes that contain variables and i have a new class that contains my arraylist. I would like to know how i would get the variables from the other classes into the arraylist in the new class. I know that you would use the add methods, but am unsure of the code to do it.

Example code would be very useful.

Thanks

Thanks for the Help.

However i forgot to mention that the classes that contain the variables, are in constructors. And now i am getting errors saying 'cannot find symbol - constructor classA'. What can i do to overcome this error.

Thanks

can u plz send me your code....then i may be able to help you better...

HI, this is the code for my first class, which contains the variables and constructor. Then i have several other classes that contain the same kind of code:

import java.util.Scanner;

public class Details
{
    Scanner console = new Scanner(System.in);

    public String name;
    public int age;

    public Details(String Name, int Age)    
    {
        name = Name;
        age = Age;
    } 

    public String getname()
    {
        return name;
    }

    public int getage()
    {
        return age;
    }

Then i have the class that contains the arraylist:

import java.util.ArrayList;

public class arrayList 
{
    public static void main(String[] args)
    {
        List<Details> list = new ArrayList<Details>();

        Details a = new Details();
        list.add(Details.name);
        list.add(Details.age);

        System.out.println(list);
    }
}

try this.....actually the problem was....u were instantiating ur Details classes with passing any argument and in your Details clas u didnt had any such constructor defined.....now i hope this will work fine.

import java.util.Scanner;

public class Details {
Details(){

}
Scanner console = new Scanner(System.in);

public String name;

public int age;

public Details(String Name, int Age) {
name = Name;
age = Age;
}

public String getname() {
return name;
}

public int getage() {
return age;
}
}


import java.util.ArrayList;
import java.util.List;

public class arrayList
{
public static void main(String[] args)
{
List list = new ArrayList();

Details a = new Details();
list.add(a.name);
list.add(a.age);

System.out.println(list);
}
}

Thanks for the Help, have got it working now.

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