All array objects have one built-in public variable to determine the length of an array.
Syntax:
arrayName.length
double[] studentAvgs = new double[5]; //declare & allocate an array object String[] strings = new String[10]; Student[] students = new Student[3]; System.out.println(studentAvgs.length); //This will print 5 System.out.println(strings.length); //This will print 10 System.out.println(students.length); //This will print 3 //2D array double[][] numbers = new double[3][5]; System.out.println(numbers.length); //This will print 3