![Examples of
ArrayList
Methods
• To access an element in the ArrayList, use the get() method and
refer to the index number:
cars.get(0);
Note: Array indexes start with 0: [0] is the first element.[1] is the
second element, etc.
• To modify an element, use the set() method and refer to the index
number:
cars.set(0, "Opel");
• To remove an element, use the remove() method and refer to the
index number:
cars.remove(0);
• To remove all the elements in the ArrayList, use the clear()
method:
cars.clear();
• To find out how many elements an ArrayList have, use
the size method:
cars.size();](https://image.slidesharecdn.com/arraylist-191205054335/85/ArrayList-in-JAVA-6-320.jpg)
ArrayList in JAVA
- 1. ArrayList
- 2. ArrayList Class • The java.util.ArrayList class provides resizable array and implements the List interface. Some important points about ArrayList: It implements all optional list operations & it also permits all elements includes null. It provides method to manipulate the size of the array that is used internally to store the list. The constant factor is low compared to that for the LinkedList implementation.
- 4. JAVA ArrayList • The difference between a built-in array and an ArrayList in Java, is that the size of an array cannot be modified. • If you want to add or remove elements to/from an array, you have to create a new one. While elements can be added and removed from an ArrayList whenever you want. • The syntax is also slightly different: Create an ArrayList object called cars that will store strings: ArrayList<String> cars = new ArrayList<String>(); // Create an ArrayList object
- 5. Example • The ArrayList class has many useful methods. • In this example , use the add() method to add elements to the ArrayList:
- 6. Examples of ArrayList Methods • To access an element in the ArrayList, use the get() method and refer to the index number: cars.get(0); Note: Array indexes start with 0: [0] is the first element.[1] is the second element, etc. • To modify an element, use the set() method and refer to the index number: cars.set(0, "Opel"); • To remove an element, use the remove() method and refer to the index number: cars.remove(0); • To remove all the elements in the ArrayList, use the clear() method: cars.clear(); • To find out how many elements an ArrayList have, use the size method: cars.size();
- 7. Thank You