最近几年来，地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持，如城市管理、区划、环境整治等等，地理信息成为信息时代重要的组成部分之一； “数字地球”概念的提出，更进一步推动了作为其技术支撑的GIS的发展。 与此同时，一些学者致力于相关的理论研究，如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面，并且这两个方面构成了相互促进的发展过程。
Servlet provides a component-based, platform-independent approach to creating web-based applications that is not limited by the performance of CGI programs. Servlet has access to all Java API, including JDBC API that accesses enterprise databases.
This tutorial shows you how to use Java Servlet to develop web-based applications.
Now start to learn Servlet! This tutorial is designed for Java programmers. Before reading this tutorial, you need to understand the Java Servlet framework and its API. After completing this tutorial, you will find that you have reached the medium level of using Java Servlet, and you can advance yourself through more in-depth study and practice. Before you start reading this tutorial, it’s best to have a good understanding of the Java programming language. If you have a basic understanding of how web applications and the Internet work, it will help you understand this tutorial. 2.1.1. Who is suitable for this tutorial? ¶
2.1.2. What you need to know before reading this tutorial: ¶