Here is a quick summary of basic use; see the next sections for details.

1. Install Java. Download from http://www.oracle.com/technetwork/java/javase/downloads/. I use JDK 1.6.0_22, but any Java 6 version will work. Servlet 3.0 containers (of which Tomcat 7 is one) require Java 6, and will not work with Java 5. You want the full JDK (with compiler), not just the JRE (for running existing apps). Accept all defaults when installing. Please note that if you use 1.6.0_21, you also need to fix the Eclipse PermGen space error or Eclipse will run out of memory and crash. That is the only Java version where you have this problem.
2. Unzip Tomcat. Unzip tomcat-7.0.8-preconfigured.zip into the location of your choice. I use the top level of the C drive, which results in C:\apache-tomcat-7.0.8. Alternatively, you can download any Tomcat 7 version from the Tomcat Web site and then copy context.xml, server.xml, and web.xml into install_dir/conf. These files are annotated with comments on what modifications were done to them.
3. Install and start Eclipse. Download from http://www.eclipse.org/downloads/. Choose "Eclipse IDE for Java EE Developers", download, and unzip. Only the latest version, Eclipse 3.6 (Helios), comes with an adapter for Tomcat 7. Double click on eclipse.exe in the eclipse folder, then click on "Workbench".
4. Tell Eclipse about Tomcat. Click on Servers tab at bottom. R-click, New, Server, Apache, Tomcat v7.0, navigate to Tomcat 7 installation folder (e.g., C:\apache-tomcat-7.0.8), OK. If you don't see Servers tab, add the tab via Window, Show View, Servers.
5. Run Tomcat. Click on Servers tab at bottom. R-click on Tomcat v7.0, choose "Start". Open http://localhost/ in a browser: you will see a 404 error message, but at least the message comes from Tomcat. Then, copy the ROOT app as described in the next section, come back, and reload http://localhost/. You should now see the normal Tomcat welcome page. If you get a "port 80 is already in use" message, go to the Control Panel, Services, and stop the other server (probably IIS). Or, double click on Tomcat at the bottom and change the port from 80 to something else. But port 80 is nicer, so it is better to stop the other server instead.
6. Copy the ROOT (default) Web app into Eclipse. Eclipse forgets to copy the default apps (ROOT, examples, etc.) when it creates a Tomcat folder inside the Eclipse workspace. Go to C:\apache-tomcat-7.0.8\webapps and copy the ROOT folder. Then go to your Eclipse workspace, go to the .metadata folder, and search for "wtpwebapps". You should find something like C:\eclipse-workspace\servlets+jsp\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps (or .../tmp1/wtpwebapps if you already had another server registered in Eclipse). Go to the wtpwebapps folder and paste ROOT (say "yes" if asked if you want to merge/replace folders/files). Then reload http://localhost/ to see the Tomcat welcome page.
7. Import and test a sample Web App. Grab test-app.zip, save it, and import it into Eclipse. Use File, Import, General, Existing Projects, Select archive file. Then click Browse and navigate to test-app.zip. Click on Servers tab at bottom. R-click on Tomcat v7.0 Server, choose "Add and Remove Projects". Choose test-app project. Start Tomcat, or restart if already running. Open http://localhost/test-app/ in browser. Note that this app uses the servlet 3.0 @WebServlet annotation to provide the URLs for the various servlets. See the source code for details.
8. Create and test a new Web App. File, New, Project, Web, Dynamic Web Project. Make sure that the Target runtime is "Apache Tomcat v7.0". Copy HTML, JSP, and servlet files from the test-app project into this new project. Deploy and test it as above.
9. Tweak Eclipse preferences. Window, Preferences, then many options re font sizes, import and indentation styles, and so forth. At a minimum, suppress unnecessary warnings about Serializable classes. Window, Preferences, Java, Compiler, Errors/Warnings, change "Serializable class without ..." to "Ignore". Also, if you were already using Eclipse with an earlier Java version, go to Window, Preferences, Java, Installed JREs, and make sure the new Java version is selected.
10. Bookmark the servlet & JSP Javadocs. Add the servlet 3.0, JSP 2.2, and EL 2.2 API to your bookmarks/favorites list.
11. Learn details of servlet and JSP programming. If you got through the previous steps, Eclipse and Tomcat are all set up, and you are ready to start the fun part: learning JSP and servlet development! See these servlet and JSP programming tutorials.

Download from http://www.oracle.com/technetwork/java/javase/downloads/. Get the standard edition (Java SE), not the enterprise edition (Java EE). Be sure to get the JDK (which has a compiler), not just the JRE (which is for running preexisting applications). I use JDK 1.6.0_22, but any Java 6 version will work. Servlet 3.0 containers (of which Tomcat 7 is one) require Java 6, and will not work with Java 5. Once you have downloaded the installer, run it and accept all default settings. There is no need to set any environment variables, but if you already had an earlier version of Java installed and you had set the PATH variable (pointing at the bin subfolder) or the JAVA_HOME variable (pointing at the main installation folder), it is a good idea to update them to the new version.

Also, please note that if you use 1.6.0_21, you also need to fix the Eclipse PermGen space error or Eclipse will run out of memory and crash. That is the only Java version where you have this problem.

Unzip tomcat-7.0.8-preconfigured.zip into the location of your choice. I use the top level of the C drive, resulting in C:\apache-tomcat-7.0.8\. This preconfigured version of Tomcat has the following settings already in place.

• The port is changed from 8080 to 80. This lets you enter URLs of the form http://localhost/... instead of http://localhost:8080/....
  • When you download Tomcat from the Apache site, the port is 8080 in case you already have another server running on port 80.
• Tomcat monitors struts-config.xml and faces-config.xml. Whenever either of these files changes, Tomcat reloads the Web application. This saves you from restarting the server when you change these files.
  • If you do not use Struts or JSF, this change will not be beneficial to you. But it does not hurt either way.
• Directory listings are turned on. If you type a URL ending in / and there is no welcome file, Tomcat shows a directory listing.
  • Directory listings were on by default in previous Tomcat versions, but are off in the current version. They are convenient during development so you can just click on files, but most developers disable them for deployed applications.

Alternatively, you can download any Tomcat 7 version from the Tomcat Web site and then copy context.xml, server.xml, and web.xml into install_dir/conf. These files are annotated with comments on what modifications were done to them.

Go to http://www.eclipse.org/downloads/. Choose "Eclipse IDE for Java EE Developers", download, and unzip. Only the latest version, Eclipse 3.6 (Helios), comes with an adapter for Tomcat 7. There is no real installer, so unzipping it is all you need to do. I normally unzip into the top level of the C drive, resulting in C:\eclipse, but any location is fine.

Start Eclipse by going to the "bin" folder and double-clicking on eclipse.exe. I usually make a shortcut on the desktop by R-clicking on eclipse.exe, selecting Copy, then going to the desktop, R-clicking, and doing Paste Shortcut.

After you start Eclipse, select "Workbench" as shown on the image to the right.

First, start Eclipse and go to the Workbench as shown in the previous section. Then, click on Servers tab at bottom. (If you don't see Servers tab, add the tab via Window, Show View, Servers.) R-click on Servers tab, New, Server, Apache, Tomcat v7.0, navigate to folder, OK. You should now see "Tomcat v7.0 Server at localhost" listed under the Servers tab at the bottom.

Click on Servers tab at bottom. R-click on Tomcat v7.0, choose "Start". Open http://localhost/ in a browser: you will see a 404 error message, but at least the message comes from Tomcat. Then, copy the ROOT app as described in the next section, come back, and reload http://localhost/. You should now see the normal Tomcat welcome page.

If you fail to copy the ROOT files as mentioned below, http://localhost/ will result in a 404 error. But, the error page comes from Tomcat, so it shows that Tomcat is running. The problem is that Eclipse doesn't copy the default Web application to the Eclipse/Tomcat folder. However, if you copy the ROOT files as described in the next section, http://localhost/ will give the nice friendly "Welcome to Tomcat" page.

If you get a "port 80 is already in use" message, that means you have another server already using port 80 (probably IIS). To stop the other server, go to the Control Panel, Services, and stop it from there. Or, double click on Tomcat at the bottom of the Eclipse window and change the HTTP/1.1 port (see the upper right) from 80 to something else. But using port 80 is nicer, so it is better to stop the other server instead of changing the Tomcat port.

It is also easy to start and stop Tomcat manually, without using Eclipse. Just go to the "bin" folder of the Tomcat installation directory (e.g., C:\apache-tomcat-7.0.8\bin) and double click on startup.bat and shutdown.bat. You can also manually deploy WAR files to the "webapps" folder of the Tomcat installation directory. However, doing everything in Eclipse is much more convenient because Eclipse automatically sends over changes as you modify files.

Eclipse forgets to copy the default apps (ROOT, examples, etc.) when it creates a Tomcat folder inside the Eclipse workspace. Go to C:\apache-tomcat-7.0.8\webapps, R-click on the ROOT folder and copy it. Then go to your Eclipse workspace, go to the .metadata folder, and search for "wtpwebapps". You should find something like your-eclipse-workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps (or .../tmp1/wtpwebapps if you already had another server registered in Eclipse). Go to the wtpwebapps folder, R-click, and paste ROOT (say "yes" if asked if you want to merge/replace folders/files). Then reload http://localhost/ to see the Tomcat welcome page.

Grab test-app.zip and save it. Import it into Eclipse with File, Import, General, Existing Projects, Select archive file. Then click Browse and navigate to test-app.zip. Note that this app uses the @WebServlet annotation to give URL patterns to servlets, and will only run in Tomcat 7 or other servlet 3.0 containers. It will not run in Tomcat 6.

Click on Servers tab at bottom. R-click on Tomcat v7.0 Server, choose "Add and Remove Projects". Choose test-app. Start Tomcat, or restart it if already running (R-click on Tomcat and choose either "Start" or "Restart"). Try the following URLs in a browser:

• http://localhost/test-app/ Welcome page showing links to pages and servlets below.
• http://localhost/test-app/hello.html Simple HTML page.
• http://localhost/test-app/hello.jsp Simple JSP page.
• http://localhost/test-app/hello The HelloWorld servlet that generates plain text.
• http://localhost/test-app/test1 The TestServlet that generates HTML, accessed via the URL given in the @WebServlet annotation in the Java source code.
• http://localhost/test-app/test2 The TestServlet, accessed via the URL given in the web.xml file.

Here is a quick summary of the most commonly used folders in Dynamic Web Projects in Eclipse.

WebContent. Regular Web files (HTML, JavaScript, CSS, JSP, images, etc.) WebContent/some-subdirectory Web files in subdirectory. WebContent/WEB-INF web.xml. This deployment descriptor be used for servlet mappings and many other tasks. However, this file can be completely omitted in servlet 3.0 apps, since servlet mappings can be done via the @WebServlet annotation in the Java source code. WebContent/WEB-INF/lib JAR files specific to application. src/testPackage Java code in testPackage package. Make a package by R-clicking on "Java Resources: src" and doing New, package. Always make packages: use of the default package is strongly discouraged in Web apps. Note: You can cut/paste or drag/drop existing files into the appropriate locations.

Follow same procedure as given in example above with "test-app" app: Click on Servers tab at bottom. R-click on Tomcat v7.0 Server, choose "Add and Remove Projects". Choose app. Start Tomcat, or restart if already running. Open http://localhost/appName/ in browser. You must restart the server after adding a new project. To do so, R-click server and choose "Restart".

For details on writing servlets, giving them custom URLs, using JSP, applying the MVC architecture, creating JSP custom tag libraries, and many other servlet and JSP topics, please see the servlet and JSP programming tutorial.

There are many customizations you can do in Eclipse. You can adjust the font size, colors, indentation styles, import statement formats, and much much more. Go to Window, Preferences and browse around.

One customization you almost always want to do is to suppress the unneeded warning re serialVersionUID on Serializable classes. The HttpServlet class is already Serializable, but nobody actually sends instances across the network or writes them to disk, and certainly almost nobody puts in a serialVersionUID field in servlets. But, if Eclipse marks every servlet with a warning, you get in the very bad habit of ignoring warnings. Most of the warnings are actually useful; this is a rare exception. So, go to Window, Preferences, Java, Compiler, Errors/Warnings, expand "Potential programming problems", and change "Serializable class without serialVersionUID" to "Ignore".

Also, if you were already using Eclipse with an earlier Java version, go to Window, Preferences, Java, Installed JREs, and make sure the new Java version is selected.

The single most useful reference for a servlet and JSP developer is the online API. Sadly, as of October 2010, there was no online version of the servlet 3.0 and JSP 2.2 Javadocs, and browsing the massive Java EE 6 API is much more difficult because the servlet and JSP classes get lost in the crowd. So, I generated the API from the Tomcat 7 source code. You can access the result at http://docs.coreservlets.com/servlet-3.0-api/. And, if you haven't already done so long ago, bookmark the Java SE 6 API.