Removal of logic and a simple language cuts need for code
What is it?
Functionally, JSP (Java Server Pages) is quite similar to Microsoft's Active Server Pages (ASP). Both provide simplified ways of creating dynamic interactive pages within web applications, which are easy to maintain because page design and logic are separated. Both are suitable for people who are not Java or Visual Studio experts .
One major difference used to be that ASP was restricted to Microsoft platforms. But with Sun's acquisition of Chilisoft and the creation of Java System Active Server Pages, and some open source community initiatives, ASP is supported on Unix, Linux and a growing range of other platforms. However, although Microsoft has been rapidly extending and opening ASP.Net to other languages, JSP is more closely integrated into Java, with a more coherent and scalable component technology.
What is it for?
According to Sun, "JSP pages use XML tags and scriptlets written in Java to encapsulate the logic that generates the content for the page.
"It passes any formatting (HTML or XML) tags directly back to the response page.
"In this way, JSP pages separate the page logic from its design and display."
JSP pages are compiled into servlets, and can call components such as Enterprise JavaBeans to perform processing on the server.
Where did it originate?
JSP was developed by the Java Community Process, led by Sun, but also involving Apache, BEA Systems, Boeing, Borland, IBM, Macromedia, Novell and SAS.
What makes it special?
Authors simply write a page using HTML/XHTML, then add scriptlets and XML tags.
Most of the programming overhead is automatically taken care of. Because logic and presentation are separated, an author can change a page without touching the application. Applications involving JSP are scalable through the full range of systems supporting Java.
How difficult is it to master?
Straightforward for people with some experience of HTML and/or XML. The Expression Language simplifies things further.
Where is it used?
Wherever web pages need to be included in Java applications.A possibly superannuated list of users linked to Sun's JSP homepage includes "Microsoft/MSNBC" as well as BMW, IBM, Harley Davidson, Universal Studios, Ford and CNN.
What systems does it run on?
Most platforms, including Sun Solaris , Windows, Unix, Linux and Mac OS.
Apache's Tomcat isprobably the best-known JSP implementation.
What's coming up?
JSP 2.1, which addresses a mismatch between JSP 2.0 and Java Server Faces (JSF) which is used to build user interface components.
The Expression Language in JSP 2.1 has been redone for a better fit with JSF.
There's a range of how-to and other material, including topics like Developing XML Solutions with Java Server Pages Technology at the Java website . You'll also find a lot of material and support on the many Java community sites, commercial and uncommercial. JSP is covered in J2EE and other Java courses, or you can find dedicated JSP and Servlet courses from independent trainers around the country. Expect to pay around £300 a day for these courses, which last from three to five days. Also see online courses from Sun and others.
Rates of pay