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Bluetooth Essentials for Programmers in Visual Studio .NET Make PDF417 in Visual Studio .NET Bluetooth Essentials for Programmers barcode for VS .NET

Bluetooth Essentials for Programmers Using Barcode creator for VS .NET Control to generate, create bar code image in Visual Studio .NET applications.VS .NET bar code for .NET Table 5.1 Transport protocols barcode for Visual Studio .NET supported by JSR-82.

rfid Java - JSR82 RFCOMM L2CAP Both the RFCOMM and L2CAP tra barcode for .NET nsport protocols are supported in JSR-82 (see Table 5.1).

JSR-82 also speci es an API for the OBEX protocol, but in our experience this is often omitted from an implementation. For example, many (if not most) Nokia cellular phones that support JSR-82 do not implement OBEX support. Support for L2CAP may also vary, especially in Windows XP implementations that use the Microsoft Bluetooth stack (see 4 for details).

Since there is no central authority that grants permission for the use of the term JSR-82, we recommend checking the supported features on the speci c implementations for a target device to ensure that the necessary functionality is available. Note: The example applications in this section work best on a desktop or laptop computer. (Windows XP, OS X, and GNU/Linux should all be ne.

) For brevity and clarity, we ve left out all of the user interface code that would normally accompany a Java program written for cell phones or other handheld devices. Although the essentials are the same, there are several notable differences. The next section highlights these differences.

In addition, the process of device and service discovery are more tightly integrated than in the other language and system implementations covered in previous chapters (see Sections 5.2 and 5.3).

Another difference is that as each device or service is detected, a callback is invoked. A signi cantly different way of specifying devices is also something to pay attention to while reading Sections 5.4 and 5.

5 on RFCOMM and L2CAP sockets.. 5.1 Notable Differences Several functional aspects of bar code for .NET framework JSR-82 stand out from the other Bluetooth programming environments we ve seen so far, and are worth mentioning before we dive in:. Java JSR-82. Connection javax.microedition.io L2CAPConnectionNotifier javax.bluetooth StreamConnectionNotifiier javax.microedition.io L2CAPConnection javax.bluetooth StreamConnection javax.microedition.io OutputStream java.io InputStream java.io Figure 5.1 Inheritance and co bar code for Visual Studio .NET ntainment diagram for Java Bluetooth connections.

Empty triangular arrows denote inheritance, and solid diamonds indicate containment.. Sockets and connections: In a n attempt to be somewhat more intuitive, what we ve been referring to all along as sockets are referred to in Java as Connections. For example, a connected RFCOMM socket is represented by the StreamConnection interface, and a connected L2CAP socket is represented by the L2CAPConnection interface, both of which implement the Connection interface. To be consistent, we ll still call them sockets, but note that other JSR-82-related documents will probably call them connections.

Additionally, listening sockets are no longer the same data type as connected sockets. For example, a listening RFCOMM socket corresponds to a StreamConnectionNotifier, and a listening L2CAP socket corresponds to a L2CAPConnectionNotifier. The inheritance hierarchy of connection classes is illustrated in Figure 5.

1, and will be discussed in more detail later on. Service Discovery Protocol (SDP): It is not possible in JSR-82 to create a listening socket without also advertising an SDP service. At least one Service Class ID must be speci ed when creating a listening socket.

The service record can be modi ed after the corresponding listening socket has been created, but it cannot be unadvertised before the socket is closed. Dynamically assigned port numbers only: Listening sockets in JSR-82 are always dynamically assigned port numbers, and it is not possible to use. Bluetooth Essentials for Programmers programmer-assigned port numb ers. This may come across as an inconvenience for those who just want to put up a quick Bluetooth service, although it does encourage proper usage of port numbers. As a consequence, Bluetooth client applications connecting to services implemented in JSR-82 must use SDP to nd the port number used by the service.

Tighter integration of Bluetooth security: Bluetooth security is tightly integrated into JSR-82, and options for Bluetooth authentication and encryption are often built into the various connection methods. We ll see this in the examples, but the basic idea is that JSR-82 forces the programmer to consider Bluetooth security in places where other Bluetooth programming environments do not..

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