JSP（JavaServer Pages）是做Java Web开发必须掌握的语言。
JSP: JavaServer Pages is a technology for developing web pages that include dynamic content. Unlike a plain HTML page, which contains static content that always remains the same, a JSP page can change its content based on any number of variable items, including the identity of the user, the user's browser type, information provided by the user, and selections made by the user.
JSP的优势
JSP combines the most important features found in the alternatives:
JSP supports both scripting- and element-based dynamic content, and allows developers to create custom tag libraries to satisfy application-specific needs.
JSP pages are compiled for efficient server processing.
JSP pages can be used in combination with servlets that handle the business logic, the model favored by Java servlet template engines.
In addition, JSP has a couple of unique advantages that make it stand out from the crowd:
JSP is a specification, not a product. This means vendors can compete with different implementations, leading to better performance and quality. It also leads to a less obvious advantage, namely that when so many companies have invested time and money in the technology, chances are it will be around for a long time, with reasonable assurances that new versions will be backward compatible; with a proprietary technology, this is not always a given.
JSP is an integral part of J2EE, a complete platform for enterprise class applications. This means that JSP can play a part in the simplest applications to the most complex and demanding.
Separation of request processing, business logic, and presentation
几个说明
Servlet
同样必须学会。
Servlet容器
Tomcat，Jetty，JBoss，Weblogic，WebSphere等。
Tag库
会使用官方的基本可以，了解自己开发库基本可以了，自己开发的情况不多。
JDBC访问数据需要了解
可以了解几个模版引擎
Velocity和FreeMaker
正式工程，只是个前端展示，servlet基本是少不了的。
另外有兴趣的可以看看Applet，特殊场景下有使用。
推荐图书：
免费视频：
尚学堂Jsp快速入门（高淇）
http://study.163.com/course/courseMain.htm?courseId=1067001
总结
Web开发的话，好好掌握，不是的话，不需要学习！
1-2周学习即可，不要超过1个月。
欢迎加入程序员的世界，添物科技为您服务。