qr code generator crystal reports free CASE STUDY 2: A PIPELINED HTTP SERVICE in Font

Paint Quick Response Code in Font CASE STUDY 2: A PIPELINED HTTP SERVICE

CHAPTER 12 CASE STUDY 2: A PIPELINED HTTP SERVICE
QR Code Drawer In None
Using Barcode generation for Font Control to generate, create Quick Response Code image in Font applications.
www.OnBarcode.com
Creating Data Matrix In None
Using Barcode generator for Font Control to generate, create Data Matrix 2d barcode image in Font applications.
www.OnBarcode.com
public ThreadSemaphore Get(int theSequenceNumber) { return blockedRequests[theSequenceNumber] as ThreadSemaphore; } } Listing 12-18. The VB .NET Implementation of ThreadSemaphore and RequestQueue Public Class ThreadSemaphore Public requestEvent As New ManualResetEvent(False) Public sequenceNumber As Integer Public request As String Public response As Byte() Public inUse As Boolean Public startTime As DateTime Public Function Wait(ByVal theDuration As TimeSpan) As Boolean Return requestEvent.WaitOne(theDuration, True) End Function Public Sub Signal() requestEvent.Set() End Sub End Class Public Class RequestQueue Private Shared _singleton As RequestQueue Public Shared ReadOnly Property Singleton() As RequestQueue Get If singleton Is Nothing Then _singleton = New RequestQueue End If Return _singleton End Get End Property ' a pool of prebuilt semaphores used with blocked requests. ' We support up to 500 concurrent requests. The value is arbitrary Private _semaphores(500) As ThreadSemaphore ' key is SequenceNumber, value is RequestSemaphore Private _blockedRequests As New Hashtable Public Sub New() For i As Integer = 0 To _semaphores.Length - 1 Dim semaphore As New ThreadSemaphore semaphore.requestEvent = New ManualResetEvent(False) _semaphores(i) = semaphore Next End Sub
Making QR In None
Using Barcode encoder for Font Control to generate, create QR image in Font applications.
www.OnBarcode.com
Print EAN128 In None
Using Barcode creator for Font Control to generate, create GTIN - 128 image in Font applications.
www.OnBarcode.com
CHAPTER 12 CASE STUDY 2: A PIPELINED HTTP SERVICE
Barcode Creator In None
Using Barcode drawer for Font Control to generate, create Barcode image in Font applications.
www.OnBarcode.com
Drawing Barcode In None
Using Barcode encoder for Font Control to generate, create Barcode image in Font applications.
www.OnBarcode.com
Public Function Add(ByVal theSequenceNumber As Integer, ByVal theRequest As String) _ As ThreadSemaphore SyncLock (Me) Dim semaphore As ThreadSemaphore = GetFirstAvailableSemaphore() _blockedRequests.Add(theSequenceNumber, semaphore) semaphore.requestEvent.Reset() semaphore.sequenceNumber = theSequenceNumber semaphore.request = theRequest semaphore.response = Nothing semaphore.startTime = DateTime.Now Return semaphore End SyncLock End Function Function GetFirstAvailableSemaphore() As ThreadSemaphore SyncLock (Me) For Each semaphore As ThreadSemaphore In _semaphores If Not semaphore.inUse Then semaphore.inUse = True Return semaphore End If Next End SyncLock Throw New Exception("RequestQueue: No semaphores available") End Function Public Sub Remove(ByVal theSequenceNumber As Integer) SyncLock (Me) Dim semaphore As ThreadSemaphore = _ DirectCast(_blockedRequests(theSequenceNumber), _ ThreadSemaphore) _blockedRequests.Remove(theSequenceNumber) semaphore.inUse = False End SyncLock End Sub Public Function [Get](ByVal theSequenceNumber As Integer) As ThreadSemaphore Return DirectCast(_blockedRequests(theSequenceNumber), ThreadSemaphore) End Function End Class When a response is detected, class Receiver fires a Receive event to CoordinatorConnection, which then uses code to get the sleeping request thread, give it the response, and wake the thread up. Listing 12-19 shows in bold the line where the request thread s semaphore is signaled.
Code 128C Generation In None
Using Barcode generator for Font Control to generate, create USS Code 128 image in Font applications.
www.OnBarcode.com
USPS PLANET Barcode Creation In None
Using Barcode maker for Font Control to generate, create USPS PLANET Barcode image in Font applications.
www.OnBarcode.com
CHAPTER 12 CASE STUDY 2: A PIPELINED HTTP SERVICE
Denso QR Bar Code Generation In None
Using Barcode creation for Font Control to generate, create QR Code image in Font applications.
www.OnBarcode.com
QR-Code Generation In None
Using Barcode maker for Excel Control to generate, create Denso QR Bar Code image in Excel applications.
www.OnBarcode.com
Listing 12-19. Using the BlockedRequests Class to Match Responses with Requests C# void HandleResponse(Socket theSocket) { // read the response HttpResponse response = new HttpResponse(theSocket); response.Get(); // get the semaphore for the blocked request thread ThreadSemaphore semaphore = blockedRequests.Get(response.SequenceNumber); if (semaphore == null) throw new Exception("No pending request found for response"); // save the response in the semaphore semaphore.response = response.Body; // unblock the request thread waiting for this response semaphore.Signal(); } VB .NET Sub HandleResponse(ByVal theSocket As Socket) ' read the response Dim response As New HttpResponse(theSocket) response.Get() ' get the semaphore for the blocked request thread Dim semaphore As ThreadSemaphore = _blockedRequests.Get(response.SequenceNumber) If semaphore Is Nothing Then Throw New Exception("No pending request found for response") End If ' save the response in the semaphore semaphore.response = response.Body ' unblock the request thread waiting for this response semaphore.Signal() End Sub The request thread was blocked in the Send method on the bold line shown in Listing 12-20. When the thread resumes (assuming a time-out doesn t occur), the response is available as a field in the ThreadSemaphore object. The code retrieves the response from ThreadSemaphore and returns it as the result of the Send method. When the method returns, the code is running on the original thread that the caller was on.
Decoding UPC Symbol In .NET
Using Barcode decoder for .NET Control to read, scan read, scan image in .NET framework applications.
www.OnBarcode.com
Draw ANSI/AIM Code 128 In None
Using Barcode generator for Microsoft Word Control to generate, create Code 128A image in Word applications.
www.OnBarcode.com
CHAPTER 12 CASE STUDY 2: A PIPELINED HTTP SERVICE
Make Barcode In Java
Using Barcode creation for BIRT reports Control to generate, create Barcode image in BIRT applications.
www.OnBarcode.com
Scan GTIN - 12 In Java
Using Barcode scanner for Java Control to read, scan read, scan image in Java applications.
www.OnBarcode.com
Listing 12-20. Where the Send Method Blocks While Waiting for a Response C# public string Send(string theLocalPath, int theSequenceNumber, string theMessage) { ThreadSemaphore semaphore = null; lock(this) { // semaphore = blockedRequests.Add(theSequenceNumber, theMessage); } // block until the response arrives, or a timeout occurs if (!semaphore.Wait(rxTimeout)) throw new Exception("No response received"); // get the response from the semaphore byte[] response = semaphore.response; blockedRequests.Remove(theSequenceNumber); return Encoding.UTF8.GetString(response); }
Paint QR Code In VB.NET
Using Barcode generator for VS .NET Control to generate, create QR Code JIS X 0510 image in .NET applications.
www.OnBarcode.com
Creating Barcode In None
Using Barcode printer for Word Control to generate, create Barcode image in Office Word applications.
www.OnBarcode.com
Creating PDF-417 2d Barcode In None
Using Barcode maker for Excel Control to generate, create PDF-417 2d barcode image in Microsoft Excel applications.
www.OnBarcode.com
Read Barcode In C#
Using Barcode Control SDK for Visual Studio .NET Control to generate, create, read, scan barcode image in Visual Studio .NET applications.
www.OnBarcode.com
GS1 - 13 Creation In Visual Studio .NET
Using Barcode creator for Visual Studio .NET Control to generate, create EAN 13 image in .NET applications.
www.OnBarcode.com
Painting UPCA In None
Using Barcode creator for Office Excel Control to generate, create UPC A image in Excel applications.
www.OnBarcode.com
Copyright © OnBarcode.com . All rights reserved.