Proxy is done

Author: sibstark

Proxy/.vscode/launch.json

@@ -0,0 +1,28 @@
+{
+   // Use IntelliSense to find out which attributes exist for C# debugging
+   // Use hover for the description of the existing attributes
+   // For further information visit https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md
+   "version": "0.2.0",
+   "configurations": [
+        {
+            "name": ".NET Core Launch (console)",
+            "type": "coreclr",
+            "request": "launch",
+            "preLaunchTask": "build",
+            // If you have changed target frameworks, make sure to update the program path.
+            "program": "${workspaceFolder}/bin/Debug/netcoreapp2.0/Proxy.dll",
+            "args": [],
+            "cwd": "${workspaceFolder}",
+            // For more information about the 'console' field, see https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md#console-terminal-window
+            "console": "internalConsole",
+            "stopAtEntry": false,
+            "internalConsoleOptions": "openOnSessionStart"
+        },
+        {
+            "name": ".NET Core Attach",
+            "type": "coreclr",
+            "request": "attach",
+            "processId": "${command:pickProcess}"
+        }
+    ]
+}

Proxy/.vscode/tasks.json

@@ -0,0 +1,15 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "taskName": "build",
+            "command": "dotnet",
+            "type": "process",
+            "args": [
+                "build",
+                "${workspaceFolder}/Proxy.csproj"
+            ],
+            "problemMatcher": "$msCompile"
+        }
+    ]
+}

Proxy/Classes/BookStore.cs

@@ -0,0 +1,22 @@
+using System.Linq;
+
+namespace Proxy.Classes
+{
+    public class BookStore : IBook
+    {
+        PageContext db;
+        public BookStore()
+        {
+            db = new PageContext();
+        }
+        public Page GetPage(int number)
+        {
+            return db.Pages.FirstOrDefault(p => p.Number == number);
+        }
+
+        public void Dispose()
+        {
+            // dispose
+        }
+    }
+}

Proxy/Classes/BookStoreProxy.cs

@@ -0,0 +1,33 @@
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Proxy.Classes
+{
+    public class BookStoreProxy : IBook
+    {
+        List<Page> pages;
+        BookStore bookStore;
+        public BookStoreProxy()
+        {
+            pages = new List<Page>();
+        }
+        public Page GetPage(int number)
+        {
+            Page page = pages.FirstOrDefault(p => p.Number == number);
+            if (page == null)
+            {
+                if (bookStore == null)
+                    bookStore = new BookStore();
+                page = bookStore.GetPage(number);
+                pages.Add(page);
+            }
+            return page;
+        }
+
+        public void Dispose()
+        {
+            if (bookStore != null)
+                bookStore.Dispose();
+        }
+    }
+}

Proxy/Classes/IBook.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace Proxy.Classes
+{
+    public interface IBook : IDisposable
+    {
+         Page GetPage(int number);
+    }
+}

Proxy/Classes/Page.cs

@@ -0,0 +1,9 @@
+namespace Proxy.Classes
+{
+    public class Page
+    {
+        public int Id { get; set; }
+        public int Number { get; set; }
+        public string Text { get; set; }
+    }
+}

Proxy/Classes/PageContext.cs

@@ -0,0 +1,29 @@
+using System.Collections.Generic;
+
+namespace Proxy.Classes
+{
+    public class PageContext
+    {
+        public List<Page> Pages { get; set; } = new List<Page>
+        {
+            new Page
+            {
+                Id = 0,
+                Number = 0,
+                Text = "Text 1"
+            },
+            new Page
+            {
+                Id = 1,
+                Number = 1,
+                Text = "Text 2"
+            },
+            new Page
+            {
+                Id = 2,
+                Number = 2,
+                Text = "Text 3"
+            }
+        };
+    }
+}

Proxy/Program.cs

@@ -0,0 +1,26 @@
+using System;
+using Proxy.Classes;
+
+namespace Proxy
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            using (IBook book = new BookStoreProxy())
+            {
+                // read the first page
+                Page page1 = book.GetPage(1);
+                Console.WriteLine(page1.Text);
+                // read the second page
+                Page page2 = book.GetPage(2);
+                Console.WriteLine(page2.Text);
+                // return back the first page
+                page1 = book.GetPage(1);
+                Console.WriteLine(page1.Text);
+            }
+
+            Console.Read();
+        }
+    }
+}

Proxy/Proxy.csproj

@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.0</TargetFramework>
+  </PropertyGroup>
+
+</Project>

README.md

@@ -14,7 +14,7 @@ My realizations of design patterns:
  - [x] #Decorator
  - [x] #Facade
  - [x] #Flyweight
- - [ ] #Proxy
+ - [x] #Proxy
 
 - Behavioral Patterns
  - [x] #Chain of Resp.