Satya Komatineni writes that you can divide the responsibilities of the middle tier into two pieces. The first part "involves retrieving the raw data based on input parameters, massaging the data, and delivering the data in the requested format." The second piece consists of "manipulating the data stored, using certain business rules and processes. In a sense, the write operation changes the state of the database server." He looks at the requirements and options in this week's ONJava article Qualities of a Good Middle-Tier Architecture.
Our next two features highlight searching and indexing. Ashwin Jayaprakash was looking for a way to organize, search, and display more than 2,000 bookmarks. His solution is a small Java applet named SearchAssist that uses XML, XPath, Swing, and LiveConnect as well as modifications to an existing Ternary Search Tree Library and other open source utilities. In the article SearchAssist: A Portable Search Engine in Java, Ashwin describes the architecture of SearchAssist, provides code examples, and also links to the complete source and other resources.
Our java.net feature of the week is Erik Hatcher's popular Lucene Intro. Erik begins with an example of using Lucene to index text files in a particular directory and all of its subdirectories. Next he introduces you to the Analysis features of Lucene. He uses Lucene's StandardAnalyzer. Finally, Erik shows you how to parse a user query and execute a search using Lucene. These steps of indexing, analysis, and search are all you need to get started using Lucene as your search engine.
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And in this week's BEA-sponsored article we have BEA WebLogic Workshop 8.1: An Overview, a look at the significant enhancements to the basic capabilities of the Workshop IDE.
Daniel H Steinberg, editor
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Figuring out what went wrong
Reports of the "Demise of the XML Database" are dubious
I have seen the light.
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