ArrayList<Matrices> list = new ArrayList<Matrices>();
list.add( new Matrices(1,1,10) );
list.add( new Matrices(1,2,20) );
Create an array to store the objects:
ArrayList<MyObject> list = new ArrayList<MyObject>();
In a single step:
list.add(new MyObject (1, 2, 3)); //Create a new object and adding it to list.
or
MyObject myObject = new MyObject (1, 2, 3); //Create a new object.
list.add(myObject); // Adding it to the list.
If you want to allow a user to add a bunch of new MyObjects to the list, you can do it with a for loop: Let's say I'm creating an ArrayList of Rectangle objects, and each Rectangle has two parameters- length and width.
//here I will create my ArrayList:
ArrayList <Rectangle> rectangles= new ArrayList <>(3);
int length;
int width;
for(int index =0; index <3;index++)
{JOptionPane.showMessageDialog(null, "Rectangle " + (index + 1));
length = JOptionPane.showInputDialog("Enter length");
width = JOptionPane.showInputDialog("Enter width");
//Now I will create my Rectangle and add it to my rectangles ArrayList:
rectangles.add(new Rectangle(length,width));
//This passes the length and width values to the rectangle constructor,
which will create a new Rectangle and add it to the ArrayList.
}
Source: Stackoverflow.com