generate barcode in asp.net c# Understanding object/relational persistence in Java

Access Quick Response Code in Java Understanding object/relational persistence

Finally, you can generate a URI that customers will be able to use to download the BLOB, using the following code:

In listing 12.4 we are doing a lot of housekeeping to manage the lifecycle of the EntityManager and to manually manage transactions. Unless you have a specific reason to use an application-managed EntityManager, we recommend using the Session Fa ade design pattern (discussed in 12.2.3) with CMT, and a containermanaged EntityManager. The EJB 3 incarnation of session beans are lightweight POJOs, which make life easier by not requiring the developer to manage the lifecycle of entity managers or transactions.

don t adhere to the Ajax model in the traditional sense but respond in a manner that provides that illusion to the end user. In this chapter, we ll focus on the server controls that provide this functionality; the next chapter will give you some insight into how ASP.NET services such as authentication and profile are also supported. As a quick overview, let s look at the server controls you have at your disposal. Figure 4.1 Figure 4.1 The Ajax server extensions are a new set of server controls that shows the new controls that are available to complement the already powerful the ASP.NET toolbox in Visual Studio. We ll controls in the ASP.NET toolbox. cover each of these controls in this chapter by explaining when and how they should be used. Since you re reading this book (and have come this far), chances are you ve previously done some ASP.NET development. If you re looking to take an application you wrote previously and add Ajax support to it, then the next few sections should be right up your alley.

session.createCriteria(Bid.class) .createAlias("bidder", "u") .setProjection( Projections.projectionList() .add( Projections.groupProperty("u.id") ) .add( Projections.groupProperty("u.username") ) .add( Projections.count("id") ) .add( Projections.avg("amount") ) );

Interpreters of the postfix notation are often stack-based. Operands are pushed onto a stack, and when an operation is performed, its operands are popped from a stack and its result pushed back on. This has the advantage of being easy to implement and very fast. When you look at the content stream snippets extracted from a PDF file using listing 14.1, you ll see operations such as -595 0 m, where -595 and 0 are the operands (in this case, representing a translation), and where m is the operator (which will cause the cursor to move 595 points to the left and 0 points up). In iText, this syntax is generated by the PdfContentByte class. This class was introduced in section 3.1, where you used it to draw paths and text at absolute positions to create a movie calendar, for instance. One of the member variables of this object is a ByteBuffer, storing the PDF syntax until it can be put into a stream object. This stream can be added to a PDF file as the content of a page, as a form XObject, or as the appearance of an annotation. This chapter contains a series of tables listing graphics and text operators in PDF, along with the corresponding methods in the PdfContentByte class.

It is quite possible to derive one class from another in a way that means we can t treat the derived class as its base type. The derived class could change the meaning or behavior of a function with the same signature as its base, or throw errors in situations where the base promised that everything would be fine say, the base accepted parameters in the range 1 10, where the derived class accepts parameters in the range 2 5. This violates the LSP, which is a very poor design practice, but it is very easy to slip into, especially if the classes evolve independently over time.

Document document = new Document(); PdfWriter.getInstance(document, new FileOutputStream(RESULT));

<connectionStrings> <add name="LibraryConnection" connectionString= "Data Source=MYSERVER\SQLEXPRESS; Initial Catalog=Library;Integrated Security=True" /> </connectionStrings>

Session session = HibernateFactory.openSession(); Event foundEvent = eventDao.find(event.getId(), session); foundEvent.setDuration(30); eventDao.update(foundEvent, session);