Java Arraylist Jupyter Notebook

Initializing an ArrayList

with strings

import java.util.ArrayList; //import array list class

public class Main {
  public static void main(String[] args) {
    ArrayList<String> fruits = new ArrayList<String>();
    fruits.add("grapes");
    fruits.add("strawberries");
    fruits.add("blueberries");
    fruits.add("kiwi");
    fruits.add("watermelon");
    System.out.println(fruits);
  }
}

Main.main(null)

[grapes, strawberries, blueberries, kiwi, watermelon]

Accessing an Element in an ArrayList

use get() method

import java.util.ArrayList; //import array list class

public class Main {
  public static void main(String[] args) {
    ArrayList<String> fruits = new ArrayList<String>();
    fruits.add("grapes");
    fruits.add("strawberries");
    fruits.add("blueberries");
    fruits.add("kiwi");
    fruits.add("watermelon");
    System.out.println(fruits.get(3));
  }
}

Main.main(null)

kiwi

Modify ArrayList Elements

use set() method

import java.util.ArrayList; //import array list class

public class Main {
  public static void main(String[] args) {
    ArrayList<String> fruits = new ArrayList<String>();

    // add elements in the array list
    fruits.add("grapes");
    fruits.add("strawberries");
    fruits.add("blueberries");
    fruits.add("kiwi");
    fruits.add("watermelon");
    System.out.println("ArrayList: " + fruits);

    // change the element of the array list
    fruits.set(2, "pineapple");
    System.out.println("Modified ArrayList: " + fruits);
  }
}
Main.main(null)

ArrayList: [grapes, strawberries, blueberries, kiwi, watermelon]
Modified ArrayList: [grapes, strawberries, pineapple, kiwi, watermelon]

Delete ArrayList Elements

use remove() method

import java.util.ArrayList; //import array list class

public class Main {
  public static void main(String[] args) {
    ArrayList<String> fruits = new ArrayList<String>();

    // add elements in the array list
    fruits.add("grapes");
    fruits.add("strawberries");
    fruits.add("blueberries");
    fruits.add("kiwi");
    fruits.add("watermelon");
    System.out.println("ArrayList: " + fruits);

    // change the element of the array list
    fruits.remove(2);
    System.out.println("Modified ArrayList: " + fruits);
  }
}
Main.main(null)

ArrayList: [grapes, strawberries, blueberries, kiwi, watermelon]
Modified ArrayList: [grapes, strawberries, kiwi, watermelon]