• Array = a data structure used to implement a collection (list) of primitive or object reference data
• Element = a single value in the array
• Index = the position of the element in the array (starts from 0)
• Array Length = the number of elements in the array

• Array: a data structure used to implement a collection (list) of primitive or object reference data
• Element: a single value in the array
• Index: the position of the element in the array (starts from 0)
• Array Length: the number of elements in the array Is public, so can be accessed in any class Is also final, so can’t change it after array has been created
• Nested loops: Used to traverse 2D Arrays

Example of an Array

public class Test {

    public static void main(String[] args) {
 
       int[][] arr = {
          { 1, 2, 3 },
          { 4, 5, 6 },
          { 7, 8, 9 }
       };
 
       System.out.println("arr[0][0] = " + arr[0][0]);
       System.out.println("arr[1][2] = " + arr[1][2]);
       System.out.println("arr[2][1] = " + arr[2][1]);
       
    }
 
 }
 Test.main(null);

arr[0][0] = 1
arr[1][2] = 6
arr[2][1] = 8

Accessing Elements of Array

public class Test {

    public static void main(String[] args) {
 
      String[][] arr = {
         { "a", "f", "g" },
         { "b", "e", "h" },
         { "c", "d", "i" }
      };
 
      // Print the last element in the array!
       print()
    }
 
 }
 Test.main(null);

public class Test {

    public static void main(String[] args) {
  
        String[][] arr = {
            { "Atlanta", "Baltimore", "Chicago" },
            { "Australia", "Boston", "Cincinnati" },
            { "Austin", "Beaumont", "Columbus" }
        };

        String longest = arr[0][0];
        
    }
 
 }
Test.main(null);