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Create a Service Bus namespace

❶For example, in CatalogServlet the identifier of the book that a customer wishes to purchase is included as a parameter to the request.

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I suspected that I needed to have a separate class or instance? StartServiceCtrlDispatcher A typical Windows Service is basically just a program that runs in the background, with no direct interaction with the user, with a few extra required interactions with Windows.

When the program is started it must call StartServiceCtrlDispatcher , passing in a table of services to be started typically just one. The dispatcher starts another thread to run ServiceMain , then it dispatches various Windows events to the service e. Instead, the last entry in the table must have NULL pointers. Therefore, while the program doesn't need at this point the name of the service it is implementing, the field must not be NULL.

Instead, set it to an empty string. The ServiceMain callback function is invoked on another thread from the main thread, and shouldn't return until the service stops usually when Windows is shutting down, but it can also be stopped and started via a control panel. The function is passed an array of strings as an argc and argv, just like a C program's main. The first string in the array is the name of the service. In this case, it is sbnstest1.

You can then add the Microsoft Azure Libraries for Java to your project:. To send messages to a Service Bus Queue, your application instantiates a QueueClient object and sends messages asynchronously. The following code shows how to send a message for a Queue that was created through the portal. Messages sent to, and received from Service Bus queues are instances of the Message class. Message objects have a set of standard properties such as Label and TimeToLive , a dictionary that is used to hold custom application-specific properties, and a body of arbitrary application data.

An application can set the body of the message by passing any serializable object into the constructor of the Message, and the appropriate serializer will then be used to serialize the object. Alternatively, you can provide a java. The header, which includes the standard and custom application properties, can have a maximum size of 64 KB. There is no limit on the number of messages held in a queue but there is a cap on the total size of the messages held by a queue.

This queue size is defined at creation time, with an upper limit of 5 GB. The primary way to receive messages from a queue is to use a ServiceBusContract object. Received messages can work in two different modes: When using the ReceiveAndDelete mode, receive is a single-shot operation - that is, when Service Bus receives a read request for a message in a queue, it marks the message as being consumed and returns it to the application.

ReceiveAndDelete mode which is the default mode is the simplest model and works best for scenarios in which an application can tolerate not processing a message in the event of a failure.

To understand this, consider a scenario in which the consumer issues the receive request and then crashes before processing it. Because Service Bus has marked the message as being consumed, then when the application restarts and begins consuming messages again, it has missed the message that was consumed prior to the crash.

In PeekLock mode, receive becomes a two stage operation, which makes it possible to support applications that cannot tolerate missing messages. When Service Bus receives a request, it finds the next message to be consumed, locks it to prevent other consumers receiving it, and then returns it to the application.

After the application finishes processing the message or stores it reliably for future processing , it completes the second stage of the receive process by calling Delete on the received message. When Service Bus sees the Delete call, it marks the message as being consumed and remove it from the queue. The following example demonstrates how messages can be received and processed using PeekLock mode not the default mode.

The example below does an infinite loop and processes messages as they arrive into our TestQueue:. Service Bus provides functionality to help you gracefully recover from errors in your application or difficulties processing a message. If a receiver application is unable to process the message for some reason, then it can call the unlockMessage method on the received message instead of the deleteMessage method.

This causes Service Bus to unlock the message within the queue and make it available to be received again, either by the same consuming application or by another consuming application.

There is also a timeout associated with a message locked within the queue, and if the application fails to process the message before the lock timeout expires for example, if the application crashes , then Service Bus unlocks the message automatically and makes it available to be received again.

In the event that the application crashes after processing the message but before the deleteMessage request is issued, then the message is redelivered to the application when it restarts. This is often called At Least Once Processing ; that is, each message is processed at least once but in certain situations the same message may be redelivered. If the scenario cannot tolerate duplicate processing, then application developers should add additional logic to their application to handle duplicate message delivery.

This is often achieved using the getMessageId method of the message, which remains constant across delivery attempts.

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How to create a windows service from java app. Yet another answer is Yet Another Java Service Wrapper, this seems like a good alternative to Java Service Wrapper as has better licensing. It is also intended to be easy to move from JSW to YAJSW. I thought about writing a service in C#, but my time constraints were too tight. share.

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