Plain Old Java Objects (POJOs) are simple Java objects that do not implement framework-specific interfaces such as those defined by the EJB framework. Java developers use POJOs to separate an application’s business logic from infrastructure frameworks, which constantly evolve. POJOs are frequently used for data persistence—the storage and retrieval of data—in Java applications.
Actuate BIRT Designer supports the use of POJOs as a data source for reports. As with other types of data sources, such as databases, XML files, and web services, for a report to use data from a POJO, you must create the following BIRT objects:
No programming is required to create these BIRT objects. However, if using POJOs created by another developer, a basic understanding of what the classes do and the data they provide is necessary. A simple POJO example typically consists of the following classes:
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A class that describes the data object, for example, a books class that describes the properties of books, including book title, author, publisher, year published, and so on.
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A class that specifies how to retrieve data. For example, such a class can retrieve data about each book by using the Java interface, Iterator, and implementing the open( ), next( ), and close( ) methods to iterate through all the book objects.
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