ArrayLists and Lists

Lists and ArrayLists in Java programming are objects that store other objects inside of them, they are very useful for storing data in multiple levels.

A usual object can store data inside of it as well as objects but ArrayLists keep the data organized in a deeper level. They are somewhat like normal arrays (String[]) however they are elastic instead of solid, meaning that they can increase and decrease in size depending on how much is required, instead of in a set amount.

public static void main(String[]args){

ArrayList<String> names = new ArrayList();// This is an example of instantiating an array list

List<String> moreNames = new ArrayList();//Lists and ArrayLists are similar however ArrayLists //are child objects from the List class. Thus the ArrayList class contains all of the previous methods //and more.

names.add("Joseph");//This is how to add a new object to an array list, it returns a boolean: true;

names.add("Smigla");

names.add(0, "Edward");//This adds a new object in the place of what ever is located in the index 

           //and moves the object in that index to the index higher than itself

           // The array will end up as: Edward, Joseph.

names.remove(1);//This removes an object from the array and and if it is larger than the index it //moves all objects after it downward an index unit, it also returns the object.

for(String n: names){System.out.print(n + " ");}//This will print in the console the objects in the list:

// Edward Smigla

}