Have you ever wanted to develop JSP Web applications? This article will help you get all the tools you need installed on your computer, and walk you through the process of writing a simple application. It is excerpted from the book Beginning JSP 2 From Novice to Professional, written by Peter den Haan et al (Apress, 2004; ISBN: 1590593391).
Creating Your First JSP Page - Downloading Tomcat (Page 2 of 7 )
This book has been written for the latest incarnation of the Apache Foundation’s Tomcat Web server, which is version 5.0. However, Tomcat 5.0 wasn’t quite ready for release at the time of this writing, so we can’t provide a definitive URL for downloading it. A good place to start is at the following URL:
This URL should open a page with (among other things) assorted links under the headings of Release Builds, Milestone Builds, and Nightly Builds. Look for anything starting with Tomcat 5 in the Release Builds section, and click it. In the event that there’s no release build of Tomcat 5, download the latest Tomcat 5 release under the Milestone Builds heading or try the following URL:
The Tomcat 5 link takes you to a screen that begins with a file listing. Click the folder marked bin, and from the list of files that then appear, Windows users should select the latest version of Tomcat 5 that ends with .exe, and Linux users should download the latest version ending with .tar.gz.
NOTE Don’t download any files that have LE in the filename because this indicates the Light Edition of Tomcat. Although the Light Edition avoids downloading duplicate copies of libraries that are now included in the 1.4 version of J2SE, it also excludes two libraries, JavaMail and the Java Activation Framework, that you’ll use later in this book.
Installing Tomcat on Windows
Just as with Java, all you need to do to install Tomcat is double-click the file you’ve downloaded. You’ll need to select a directory for the installation, such as C:\java\tomcat50. As with Java, you’ll need to remember this location for later use. Don’t click the NT Service checkbox if you see it. This option means that Windows will start Tomcat automatically every time the system boots up and stop it when Windows shuts down. This is really only useful when Web applications are finished, rather than when applications are being created, as in this book.
Installing Tomcat on Linux
To install Tomcat, you’ll need to create a suitable directory with the mkdir command and extract Tomcat into that directory with the following command (assuming you’re in the same directory where you downloaded Tomcat):
tar -xzf jakarta-tomcat-5.0.16.tar.gz -C /usr/local/java/tomcat50
Of course, change the names of the file and directory as appropriate.
Configuring Your Environment
The final step of the installation is to set some environment variables that applications can use to find components required for proper operation. Tomcat needs you to set two environment variables, and you’ll also modify the PATH variable so that the Java and Tomcat files are accessible from any other folder.
To configure Windows 2000/XP, follow these steps:
Open the System item in Control Panel, and select the Advanced tab.
Click the Environment Variables button to open the Environment Variables dialog box. You should see a window like the one shown in Figure 1-1.
Figure 1-1.The Environment Variables dialog box
3. Click the New button in the lower System Variables section. When the New System Variable dialog box appears, enter a name of JAVA_HOMEand enter the full path to your JDK (such as C:\java\jdk1.4) for the value.
4. Repeat step 3 to create another variable; call it CATALINA_HOME, the value of which specifies the location of your Tomcat installation (such as C:\java\tomcat50).
5. Create one last variable by following the same process. Call it CLASSPATH, and give it a value of %CATALINA_HOME% \common\ lib\servlet.jar;.
NOTE If you already have an environment variable called CLASSPATH, place the previous value at the end of the existing value, with a semicolon (;) at the end of the old value and before the value given in step 5.
6. Locate the variable named Path in the System Variables list, and double-click it or click the Edit button to open the Edit System Variable dialog box.
Chances are, a few different paths are already given for this variable, each path separated by a semicolon. Select the value box, and press the End key on your keyboard. Type the following, including the semicolon at the beginning:
7. Once you’re done, click OK to close the Edit System Variable window, and click OK a couple more times to close the Environment Variables and System Properties dialog boxes.
Red Hat Linux
Red Hat Linux’s default shell is the popular Bourne Again Shell (or bash). If this is your shell, you’ll need to edit your account’s startup script. To do this, log in under your own account (usually not root), and add the following lines to the~/.bashrc file using your editor of choice: