Java Example

• networks

  • networks/Facebook.java

    package refactoring_guru.template_method.example.networks;
    
    /**
     * Class of social network
    */
    public class Facebook extends Network {
        public Facebook(String userName, String password) {
            this.userName = userName;
            this.password = password;
        }
    
        public boolean logIn(String userName, String password) {
            System.out.println("\nChecking user's parameters");
            System.out.println("Name: " + this.userName);
            System.out.print("Password: ");
            for (int i = 0; i < this.password.length(); i++) {
                System.out.print("*");
            }
            simulateNetworkLatency();
            System.out.println("\n\nLogIn success on Facebook");
            return true;
        }
    
        public boolean sendData(byte[] data) {
            boolean messagePosted = true;
            if (messagePosted) {
                System.out.println("Message: '" + new String(data) + "' was posted on Facebook");
                return true;
            } else {
                return false;
            }
        }
    
        public void logOut() {
            System.out.println("User: '" + userName + "' was logged out from Facebook");
        }
    
        private void simulateNetworkLatency() {
            try {
                int i = 0;
                System.out.println();
                while (i < 10) {
                    System.out.print(".");
                    Thread.sleep(500);
                    i++;
                }
            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }
        }
    }

  • networks/Network.java

    package refactoring_guru.template_method.example.networks;
    
    /**
     * Base class of social network.
    */
    public abstract class Network {
        String userName;
        String password;
    
        Network() {}
    
        /**
         * Publish the data to whatever network.
         */
        public boolean post(String message) {
            // Authenticate before posting. Every network uses a different
            // authentication method.
            if (logIn(this.userName, this.password)) {
                // Send the post data.
                boolean result =  sendData(message.getBytes());
                logOut();
                return result;
            }
            return false;
        }
    
        abstract boolean logIn(String userName, String password);
        abstract boolean sendData(byte[] data);
        abstract void logOut();
    }

  • networks/Twitter.java

    package refactoring_guru.template_method.example.networks;
    
    /**
     * Class of social network
    */
    public class Twitter extends Network {
    
        public Twitter(String userName, String password) {
            this.userName = userName;
            this.password = password;
        }
    
        public boolean logIn(String userName, String password) {
            System.out.println("\nChecking user's parameters");
            System.out.println("Name: " + this.userName);
            System.out.print("Password: ");
            for (int i = 0; i < this.password.length(); i++) {
                System.out.print("*");
            }
            simulateNetworkLatency();
            System.out.println("\n\nLogIn success on Twitter");
            return true;
        }
    
        public boolean sendData(byte[] data) {
            boolean messagePosted = true;
            if (messagePosted) {
                System.out.println("Message: '" + new String(data) + "' was posted on Twitter");
                return true;
            } else {
                return false;
            }
        }
    
        public void logOut() {
            System.out.println("User: '" + userName + "' was logged out from Twitter");
        }
    
        private void simulateNetworkLatency() {
            try {
                int i = 0;
                System.out.println();
                while (i < 10) {
                    System.out.print(".");
                    Thread.sleep(500);
                    i++;
                }
            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }
        }
    }

• Demo.java

  package refactoring_guru.template_method.example;
  
  import refactoring_guru.template_method.example.networks.Facebook;
  import refactoring_guru.template_method.example.networks.Network;
  import refactoring_guru.template_method.example.networks.Twitter;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  
  /**
   * Demo class. Everything comes together here.
   */
  public class Demo {
      public static void main(String[] args) throws IOException {
          BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
          Network network = null;
          System.out.print("Input user name: ");
          String userName = reader.readLine();
          System.out.print("Input password: ");
          String password = reader.readLine();
  
          // Enter the message.
          System.out.print("Input message: ");
          String message = reader.readLine();
  
          System.out.println("\nChoose social network for posting message.\n" +
                  "1 - Facebook\n" +
                  "2 - Twitter");
          int choice = Integer.parseInt(reader.readLine());
  
          // Create proper network object and send the message.
          if (choice == 1) {
              network = new Facebook(userName, password);
          } else if (choice == 2) {
              network = new Twitter(userName, password);
          }
          network.post(message);
      }
  }

  Input user name: Jhonatan
  Input password: qswe
  Input message: Hello, World!
  
  Choose social network for posting message.
  1 - Facebook
  2 - Twitter
  2
  
  Checking user's parameters
  Name: Jhonatan
  Password: ****
  ..........
  
  LogIn success on Twitter
  Message: 'Hello, World!' was posted on Twitter
  User: 'Jhonatan' was logged out from Twitter