Question

Write an application that simulates coin tossing. Let the program toss a coin each time the user chooses the “Toss Coin” menu option. Count the number of times each side of the coin appears. Display the results. The program should call a separate method flip that takes no arguments and returns a value from a Coin enum (HEADS and TAILS). [Note: If the program realistically simulates coin tossing, each side of the coin should appear approximately half the time.]

Short answer

To solve this exercise, create a text menu with options to toss a coin or view results. Define a Coin enum for HEADS/TAILS and implement a flip method to randomly return one. Update and display flip counts based on user input, aiming for an approximate 50/50 distribution.

Step-by-step solution

- Design the Menu

First, design a simple text-based menu for the user to interact with. This menu should have options to 'Toss Coin', 'Show Results', and 'Exit'. The program will display this menu in a loop, processing the user's choice each time.

- Create the Coin Enum

Define an enum named 'Coin' that represents the two sides of a coin. It should have two values: HEADS and TAILS. This will be used to return the result of a single coin toss.

- Implement the flip Method

Implement a method named 'flip' that randomly selects between the HEADS and TAILS values of the Coin enum. The method should have no arguments and return a Coin value. Use the Random class to generate a 0 or 1, where 0 represents HEADS and 1 represents TAILS.

- Initialize Counter Variables

Declare and initialize two counter variables, one for counting the number of HEADS and another for TAILS. These will be incremented whenever the respective side of the Coin is returned by the flip method.

- Read User Input

Prompt the user to choose an option from the menu and read their input. Make sure the program can handle user choices and any invalid input gracefully.

- Perform Action Based on User Choice

Implement a switch/case or if-else statement to perform actions based on the user's menu choice. If the user chooses to toss the coin, call the flip method and update the counters accordingly. If 'Show Results' is chosen, display the current counts. If 'Exit' is chosen, terminate the loop and end the program.

- Display Results

Create a method to display the number of times each side of the coin has appeared. After each toss, or when the user chooses to show results, this method will print the counts to the console.

- Test the Program

Test the program to ensure that it responds correctly to user input, that the coin tosses appear to be random and that the counts displayed reflect the number of tosses correctly.

Key concepts

Java programming

Java is a widely-used programming language that is designed for portability and cross-platform compatibility. It is a high-level, object-oriented language which allows developers to create robust, multi-threaded programs with ease. Our exercise involves writing a Java application to simulate a coin toss, making it a perfect example to illustrate basic principles of Java programming, such as creating user interfaces, utilizing control structures like loops and conditionals, and working with Java's Random class for generating random numbers.

Java programs are structured around classes and methods, and a typical Java program starts with a 'public static void main' method. This coin toss simulator uses a menu in a loop to handle user input – a common practice for Java applications needing simple interaction with users. Not only do Java programs handle tasks like random number generation efficiently, but they also encourage good programming practices, like creating specific methods for specific tasks, which is seen in the implementation of the 'flip' method in our exercise.

enum types in Java

Enums, short for enumerated types, are a powerful feature in Java used to define collections of constants under a single type. In our coin toss simulation program, the enum 'Coin' is created to represent the two possible outcomes of a coin toss – HEADS and TAILS. Enums are especially useful in this scenario because they enhance code readability and type safety.

Enums are to be static and final implicitly, meaning that the instantiation of new objects is not allowed and the instance can't be changed once created. Since enums are classes, they can have fields, constructors, and methods. Java ensures that the enumeration constants are instances of their enum type, which can be used in switch statements, enhancing the clarity of your code. For instance, when the 'flip' method returns an enum value, we can use a switch statement to handle the different outcomes that the 'flip' method may return. Utilizing enums increases maintainability and readability of your Java code which is beneficial for both novices and seasoned developers alike.

method implementation in Java

Method implementation is a core concept of Java programming. In the context of our coin tossing application, we define a 'flip' method that encapsulates the logic for simulating a coin toss. Methods are blocks of code that perform a specific task, and they are called upon to execute when needed, providing code reusability and better organization.

In Java, methods must be declared within a class and can have various modifiers that govern their accessibility and behavior. The 'flip' method is defined without parameters, indicating that it requires no input to perform its action. It returns an enum type, 'Coin', showcasing how methods can return custom data types. Furthermore, Java methods can be overloaded by having the same method name but with different parameters; this technique is not used in this exercise but is very common in Java development. The implementation of the 'flip' method in our program involves the use of the 'Random' class to generate a pseudo-random number, determining the outcome of the coin toss. This approach illustrates how Java's standard library classes can be leveraged to implement method logic effectively and efficiently.