Autoboxing and foreach
In this exercise, you will explore autoboxing and looping of a List - specifically a LinkedList of prices. You will add some double to the LinkedList and allow autoboxing to convert them to Double, and use the "foreach" loop to get the average price of the prices in the LinkedList.
This exercise is part of the course
Data Types and Exceptions in Java
Exercise instructions
- Construct a new
LinkedListofDoubles and set thepricesvariable to it. - Add a new price (a
double)9.65to the end of thepriceslist. Autoboxing will automatically convert thedoubleto aDoublebefore adding it. - Add a new price (a
double)1.35to the beginning of thepriceslist. Autoboxing will automatically convert thedoubleto aDoublebefore adding it. - Use a "foreach" loop to iterate through and sum all prices.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
import java.util.LinkedList;
public class Averaging {
public static void main(String[] args) {
// Create a LinkList of Doubles using parameterized constructor
____<____> prices = ____ ____<____>();
prices.add(5.60);
// Add 9.65 to the end of the list
prices.____(____);
prices.add(3.40);
// Add 1.35 to the start of the list
prices.____(____);
System.out.println(prices);
Double total = 0.0;
// Use for each to loop through all the prices
____ (____ price : ____) {
total += price;
}
System.out.println("Average price: " + total/prices.size());
}
}