WickedProduction
9/27/2019 - 11:16 PM

ArrayLists

import java.util.ArrayList;

public class Main {

    public static void main(String[] args) {

        ArrayList<String> strings = new ArrayList<>(4); //Can add 4 elements without reallocation
        System.out.println(strings.size()); //Like .length()
        strings.add("Vehicle"); //Add elements
        strings.add("Dolphin");
        strings.add("Jordan Peterson");
        strings.add("Booty");
        strings.add(1, "New Dolphin"); //Choose WHERE to put the elements
        System.out.println(strings.size());

        //Print out the contents of the array list
        System.out.println(strings);

        //Remove elements too
        strings.remove("Jordan Peterson"); //Remove it by its value/object
        strings.remove(3); //Remove by index
        System.out.println(strings);

        //Set capacity equal to the number of elements currently in the arraylist
        strings.trimToSize();

        //Convert an arraylist to a regular array
        ArrayList<Double> doubleAL = new ArrayList<>();
        doubleAL.add(2.4);
        doubleAL.add(4.0);
        doubleAL.add(213.3);
        //Double array to store our arraylist
        Double doubles[] = new Double[doubleAL.size()]; //You have to specify the length for arrays without an initial value
        doubles = doubleAL.toArray(doubles);
        for (int i = 0;i < doubles.length;i++){
            System.out.println(doubles[i]);
        }
        
    }
}