How to get a value inside an ArrayList java ?

Retrieve value from ArrayList in java
How to get Value from ArrayList

how to add new ArrayLists and ADD value to that particular ArrayList and how to RETRIEVE the data form that list.

    ArrayList<ArrayList<Integer>> arrayList=new ArrayList<ArrayList<Integer>>();
    ArrayList<Integer> newAL= new ArrayList<Integer>();
    arrayList.add(newAL);
    newAL.add(1);
    newAL.add(2);
    newAL.clear();      
    System.out.println(arrayList.get(0));
    //Changes persist in your arraylist

So after adding ArrayList you can manipulate newAL as ArrayList stores reference you don't need to fetch and set element from main arrayList.

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To retrive data you can Iterate(Use ForEach Loop) over arrayList or you can do following

    Integer List0Item1=arrayList.get(0).get(1);//Get first element of list at 0
    arrayList.get(0).set(0, 10);//set 0th element of list at 0 as 10
    ArrayList<Integer> list10=arrayList.get(10);//get arraylist at position 10

For Example:-

main class

public class Test {
    public static void main (String [] args){
        Car thisCar= new Car ("Toyota", "$10000", "2003");  
        ArrayList<Car> car= new ArrayList<Car> ();
        car.add(thisCar); 
        processCar(car);
    } 

    public static void processCar(ArrayList<Car> car){
        for(Car c : car){
            System.out.println (c.getPrice());
        }
    }
}

car class

public class Car {
    private String vehicle;
    private String price;
    private String model;

    public Car(String vehicle, String price, String model){
        this.vehicle = vehicle;
        this.model = model;
        this.price = price;
    }

    public String getVehicle() {
        return vehicle;
    }

    public String getPrice() {
        return price;
    }

    public String getModel() {
        return model;
    }  
}