Update adapter example

Author: nemanjarogic

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/BillingSystemExecutor.cs

@@ -5,10 +5,10 @@ namespace AdapterLibrary.BillingSystemExample;
 public static class BillingSystemExecutor
 {
     /// <summary>
-    /// The client code doesn’t get coupled to the concrete adapter class as long as it works with the adapter
-    /// via the client interface. Thanks to this, you can introduce new types of adapters into the program without
-    /// breaking the existing client code. This can be useful when the interface of the service class gets
-    /// changed or replaced: you can just create a new adapter class without changing the client code.
+    /// The client code doesn't get coupled to the concrete adapter class as long as it works with the adapter via the client interface.
+    /// Thanks to this, you can introduce new types of adapters into the program without breaking the existing client code.
+    /// This can be useful when the interface of the service class gets changed or replaced:
+    /// you can just create a new adapter class without changing the client code.
     /// </summary>
     public static void Execute()
     {
@@ -18,9 +18,10 @@ public static void Execute()
         string[,] employeesInfo = hrSystem.GetEmployeesInfo();
 
         // Existing HR system wants to process salaries,
-        // but since it isn't compatible with third party billing system interface we must use adapter
+        // but since it isn't compatible with the 3rd party billing system interface we must use adapter.
+        // The 3rd party billing system expects List<Employee>, but the current HR system works only with string[,].
+        // Hide that using adapter design pattern (note that the client is not aware of what's happening under the hood).
         ISalaryProcessor salaryProcessor = new HRSystemAdapter();
-
         salaryProcessor.ProcessSalaries(employeesInfo);
     }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/Employee.cs

@@ -3,8 +3,6 @@
 public class Employee
 {
     public int Id { get; set; }
-
-    public string Name { get; set; }
-
+    public string Name { get; set; } = string.Empty;
     public decimal Salary { get; set; }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/HRSystem.cs

@@ -2,19 +2,17 @@
 
 /// <summary>
 /// This class contains the functionality which the client requires,
-/// but it’s not compatible with the existing client code.
+/// but it's not compatible with the existing client code.
 /// So, it requires some adaptation before the client code can use it.
 /// </summary>
 public class HRSystem
 {
-    public string[,] GetEmployeesInfo()
-    {
-        return new string[4, 3]
+    public string[,] GetEmployeesInfo() =>
+        new string[4, 3]
         {
             { "1", "John", "5950" },
             { "2", "Anna", "5800" },
             { "3", "Nicole", "6100" },
             { "4", "Steven", "5000" },
         };
-    }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/HRSystemAdapter.cs

@@ -1,4 +1,6 @@
-namespace AdapterLibrary.BillingSystemExample;
+using System.Globalization;
+
+namespace AdapterLibrary.BillingSystemExample;
 
 /// <summary>
 /// This is a class which makes two incompatible systems to work together.
@@ -19,48 +21,46 @@ public HRSystemAdapter()
     public void ProcessSalaries(string[,] rawEmployees)
     {
         var employeesForProcessing = PrepareEmployeesForSalaryProcessing(rawEmployees);
-
         _thirdPartyBillingSystem.ProcessSalary(employeesForProcessing);
     }
 
     private List<Employee> PrepareEmployeesForSalaryProcessing(string[,] rawEmployees)
     {
         var employeesForProcessing = new List<Employee>();
 
-        for (int i = 0; i < rawEmployees.GetLength(0); i++)
+        for (var i = 0; i < rawEmployees.GetLength(0); i++)
         {
-            string id = null;
-            string name = null;
-            string salary = null;
+            var id = string.Empty;
+            var name = string.Empty;
+            var salary = string.Empty;
 
-            for (int j = 0; j < rawEmployees.GetLength(1); j++)
+            for (var j = 0; j < rawEmployees.GetLength(1); j++)
             {
-                if (j == 0)
-                {
-                    id = rawEmployees[i, j];
-                }
-                else if (j == 1)
+                switch (j)
                 {
-                    name = rawEmployees[i, j];
-                }
-                else
-                {
-                    salary = rawEmployees[i, j];
+                    case 0:
+                        id = rawEmployees[i, j];
+                        break;
+                    case 1:
+                        name = rawEmployees[i, j];
+                        break;
+                    default:
+                        salary = rawEmployees[i, j];
+                        break;
                 }
             }
 
             var employee = new Employee
             {
-                Id = Convert.ToInt32(id),
+                Id = Convert.ToInt32(id, CultureInfo.InvariantCulture),
                 Name = name,
-                Salary = Convert.ToDecimal(salary),
+                Salary = Convert.ToDecimal(salary, CultureInfo.InvariantCulture),
             };
-
             employeesForProcessing.Add(employee);
         }
 
         Console.WriteLine("Adapter converted array of employees to list of employees...");
 
         return employeesForProcessing;
     }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/ISalaryProcessor.cs

@@ -5,5 +5,5 @@
 /// </summary>
 public interface ISalaryProcessor
 {
-    void ProcessSalaries(string[,] employees);
-}
+    void ProcessSalaries(string[,] rawEmployees);
+}

src/StructuralPatterns/Adapter/AdapterLibrary/BillingSystemExample/ThirdPartyBillingSystem.cs

@@ -8,9 +8,9 @@ public class ThirdPartyBillingSystem
 {
     public void ProcessSalary(List<Employee> employees)
     {
-        foreach (Employee employee in employees)
+        foreach (var employee in employees)
         {
             Console.WriteLine($"EUR {employee.Salary} salary credited to {employee.Name}'s account.");
         }
     }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/Executor.cs

@@ -13,4 +13,4 @@ public override void Execute()
         BillingSystemExecutor.Execute();
         MovieBroadcasterExecutor.Execute();
     }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/MovieBroadcasterExample/BroadcastAdapter.cs

@@ -4,7 +4,7 @@
 namespace AdapterLibrary.MovieBroadcasterExample;
 
 /// <summary>
-/// There is no way to pass an xDocument from registry to the third party broadcaster,
+/// There is no way to pass an xDocument from the registry to the third party broadcaster,
 /// so we need to create the adapter, which will make these two parties work together.
 /// </summary>
 public class BroadcastAdapter : IBroadcaster
@@ -21,29 +21,29 @@ public BroadcastAdapter(MovieRegistry movieRegistry)
     public void BroadcastToExternalPartners()
     {
         string jsonMovies = ConvertRegistryMoviesToJson();
-
         _thirdPartyBroadcaster.Broadcast(jsonMovies);
     }
 
     private string ConvertRegistryMoviesToJson()
     {
         XDocument xmlMovies = _movieRegistry.GetAll();
-
-        Console.WriteLine("Movies from internal registry...");
+        Console.WriteLine("Movies from the internal registry...");
         Console.WriteLine(xmlMovies);
 
         IEnumerable<Movie> modelMovies = xmlMovies
-            .Element("Movies")
+            .Element("Movies")!
             .Elements("Movie")
             .Select(movie => new Movie
             {
-                Name = movie.Attribute("Name").Value,
-                ReleaseDate = DateTime.Parse(movie.Attribute("ReleaseDate").Value),
-                Rating = Convert.ToDouble(movie.Attribute("Rating").Value),
+                Name = movie.Attribute(nameof(Movie.Name))!.Value,
+                ReleaseDate = DateTime.Parse(movie.Attribute(nameof(Movie.ReleaseDate))!.Value),
+                Rating = Convert.ToDouble(movie.Attribute(nameof(Movie.Rating))!.Value),
             });
 
         string jsonMovies = JsonConvert.SerializeObject(modelMovies, Formatting.Indented);
+        Console.WriteLine("\nMovies from the internal registry are converted to JSON format");
+        Console.WriteLine(jsonMovies);
 
         return jsonMovies;
     }
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/MovieBroadcasterExample/IBroadcaster.cs

@@ -3,4 +3,4 @@
 public interface IBroadcaster
 {
     void BroadcastToExternalPartners();
-}
+}

src/StructuralPatterns/Adapter/AdapterLibrary/MovieBroadcasterExample/Movie.cs

@@ -2,9 +2,7 @@
 
 public class Movie
 {
-    public string Name { get; set; }
-
+    public string Name { get; set; } = string.Empty;
     public DateTime ReleaseDate { get; set; }
-
     public double Rating { get; set; }
-}
+}