Dynamic Web-based data access using JSP and JDBC technologies
This article discusses using the JSP and JDBC technologies to integrate static, dynamic, and database content in Web sites. For the purposes of simplicity and illustration, the JSP pages here use short scriptlets to expose the JSP developer to the underlying JDBC concepts instead of hiding them in custom tags. The author introduces a key design approach that integrates JavaBeans components with JDBC, similar to the way that JavaServer Pages technology already uses beans with HTTP. He also provides code for implementing this integration.
Building on the Java Servlet technology, JavaServer Pages (JSP) technology is the core server-side Java architecture for generating dynamic content. One source of dynamic content is the relational database. To manage everything from online communities to e-commerce transactions, Web sites use relational databases to store all sorts of information: catalog items, images, text, data about registered members, and so on. This article discusses the application of JSP technology to relational databases through Java Database Connectivity (JDBC). JDBC is the means by which Java programs work with relational databases.
To get the most out of this article, you should be familiar with JDBC and SQL.
JDBC basics
JDBC is the bridge between Java code and SQL databases. The primary JDBC objects represent connections to a database and the statements performed using those connections. The two basic kinds of statements used with a relational database are 本文来自优.文,论-文&网原文请找腾讯752018766 java.sql.DriverManager class. Connections take a long time (in computer time) to establish, so in a transaction-intensive environment like a Web server, you want to reuse connections whenever possible. Such reuse is called connection pooling.
In real life, JDBC code is not this simple; exceptions and warning conditions need to be handled. Listing 2 illustrates the same JDBC example but adds handling for JDBC exceptions and warnings. In this example, exceptions and warnings are simply logged and, in the case of exceptions, we abort the operation. However, the 2649