Jair Rillo Junior’s blog

Installing and configurating Apache Tomcat 5.5 and 6.x. (Windows and Linux)

October 24th, 2007 | Tags:

Hi There,

After a long time far away from this blog, I am here to write about Apache Tomcat.

Although this topic is simple for many people, it may be useful for whom is starting in Java Web World.

I am writing this topic because I have seen many people on Java’s forum and also some friends newbie in Java asking for this issue. Besides the basic, I am going to talk about management and datasource configuration in Apache Tomcat, as well as a Java code example to use the tomcat’s datasource.

Downloading the proper version

The Tomcat’s official website is that: http://tomcat.apache.org/. There you are going to see all information about Tomcat, as well as the version to be downloaded. If you are newbie in tomcat and would like to get more information than wrote in this topic, I encourage you to spend some time in Tomcat’s official website.

The first thing to do is download the proper version. In nowdays, basically we have two updated version: 5.5 and 6.x. What’s the difference between them?

In general speaking, the difference between them is the JEE version used. Tomcat version 6.x uses JEE 5.0 (Servlet 2.5, JSP 2.1) and Tomcat version 5.5 uses JEE 1.4 (Servlet 2.4, JSP 2.0).

If you are going to work on JEE 5.0, you must download the tomcat 6.x, otherwise you can download version 5.5. In this topic, I am going to explain how to configure both versions.

Whatever version you choose, you are going to see on download page three files (.zip, .tar.gz, Windows Service Installer). If you are installing the Tomcat in an Unix-like system, you must download the version .tar.gz. If you are installing the Tomcat in a Windows system, you can choose either .zip or Windows Service Installer file. In my opinion, I prefer the .zip file.

Installing Tomcat

In this section, let’s talk about Tomcat installation. Fortunately the installation in both Windows and Linux system is really easy.

Basically, you have to unzip the tomcat installation file and after create two environment variables. Also, you have to make sure if the JAVA_HOME environment variable is already set.

Windows Installation

Firstly, you have to unzip the Tomcat installation file in any directory. Let’s use as example the tomcat’s version 5.5.25 (for tomcat’s version 6.x, the process is exactly the same) and the directory “Programs Files“. Unzipping the tomcat’s file inside Programs Files directory, a new directory will be created, called “apache-tomcat-5.5.25“.

Now, the next step is to create two environment variables. In Windows, just click on Start button -> Settings -> Control Panel.

On the Control Panel screen, double click on System icon. A new window will be opened.

In this new window (System Properties), click on Advanced tab and after on Environment Variables button.

An Environment Variables window will be opened.

On the bottom of this window, there are some System variables such as: CLASSPATH, INCLUDE, LIB, etc. You have to create more two variables: CATALINA_HOME and CATALINA_BASE.

Click on New button and a new window will appear.

In this new window, you have to fill up both fields: Variable name and variable value.

Put the following information in these fields:
Variable name: CATALINA_HOME
Variable value: <path of Tomcat apache> in my example would be: C:\Program Files\apache-tomcat-5.5.25

Repeat the same process but putting the variable name: CATALINA_BASE and the variable value the same than CATALINA_HOME.

Before close up the Environment Variables window, make sure the JAVA_HOME is set up. If not, you must configure the JAVA_HOME (like CATALINA_HOME) but referring the path where Java was installed.

After the environment variables were defined, you will be able to start Tomcat. Simply perform the file startup.bat (it is localized inside tomcat/bin directory). A command prompt window will appear and show you the starting. If the following screen appears, your tomcat has been installed successfully.

If you got any exception on startup, try to repeat the installation process again.

Unix/Linux installation

The process in Unix/Linux is similar than Windows. Basically you have to uncompress the .tar.gz file and create two environment variables.

To uncompress the .tar.gz file in Unix/Linux system, you can use the command tar.An example would be:

tar -zxvf apache-tomcat-5.5.25.tar.gz

This command will uncompress the file apache-tomcat-5.5.25.tar.gz and also will create a directory called apache-tomcat-5.5.25. This is the directory where tomcat was installed in Linux. I advice you to use a directory where your current user has access to read/write files.

The next step, like in Windows, is create the environment variables. In Linux, you can create these variables editing the file .profile inside your home directory.

Edit this file and add the following lines:

export CATALINA_HOME="<directory where tomcat was installed>". eg: "/home/junior/apache-tomcat-5.5.25"
export CATALINA_BASE="<directory where tomcat was installed>"

Like in Windows, you have to make sure the JAVA_HOME is set.

To start the Tomcat in Linux, you have to perform the file startup.sh. This file is localized inside apache-tomcat/bin directory. Also like windows, you will see the starting in console. Any exception, try to repeat the process.

Starting up, testing and shutting down

As described above, to start the tomcat, you simply have to perform startup.bat (Windows) or startup.sh (Unix/Linux). A window will show up if the process has been startup successfully.

After tomcat was startup, it is time to test it. It is also a simple task, only open your internet browser, and try the following URL: http://localhost:8080.

You should see a screen like this:

As you can see, by default tomcat runs on port: 8080. If you want to change this port, you have to modify the file server.xml inside apache-tomcat-5.5.25/conf directory and restart the tomcat server, but the question is: How can I restart the apache tomcat?

There is no option to restart the tomcat, you must shutdown it and after that start it again.

To shutdown it, you can either stop the current process (in windows just close the command prompt) or perform the file shutdown.bat (windows) or shutdown.sh (Linux).

Tomcat Manager

When you start the tomcat and open the default page (http://localhost:8080), you have an option called Tomcat Manager in the left menu.

Inside this section, you are able to deploy a new application, undeploy an existing application, stop or start a single application, reload a context and so on.

If you try to click on this Link, an Authentication pop up will appear. In other words, to access the Tomcat manager you have to put the proper user and password. Where can I figure out this user/password?

Whatever which version you are using and which operating system you are, you have to modify the file tomcat-users.xml. By default, it brings some examples, but you have to create your own rules, anything like this:

<tomcat-users>
  <role rolename="manager"/>
  <user username="test" password="test123" roles="manager"/>
</tomcat-users>

After this file is changed, stop and start the tomcat again.

Click on Tomcat Manager and when the popup appears, put test as username and test123 as password. If your data are correct, you are going to see the Manager screen.

On this screen you are able to start, stop, reload or undeploy an application. Also, you are able to deploy a new application located on server or upload a war file and deploy it. Fell free to click on options and see what will happen.

Deploying an application without Tomcat Manager

You already learned how to deploy a WAR file using Tomcat Manager, however you are free to deploy an application without it as well.

Inside apache-tomcat directory, there is a directory called “webapps“. All application deployed are localized in this directory.

You are able either to copy your application for this directory directly or copy your .war file inside it. When Tomcat starts, it will read this directory and make the deploy automatically.

Another option for deploying is to use an external tool. You can use ANT or MAVEN to make the deploy or use a plugin for Eclipse, such as: WTP, TomcatPlugin, MyEclipseIDE, etc.

Creating a DataSource in Apache Tomcat

In real applications, it is recommended to use a Connection Pool to management of your connection with database. Whatever application server you are using, you have to create a DataSource to use a connection pool. Each application server has a different way to create a DataSource. In this topic I am going to show you how to create it in Apache Tomcat (in the future I will write a post about DataSource in Websphere 6.0).

Fortunately in Apache Tomcat the process to create a DataSource is simple. Basically you have to create/modify a file called context.xml.

If you want a global datasource, it means a datasource will be eligable for all application, you have to modify the file context.xml localized in apache-tomcat-5.5.25/conf.

If you want a specific datasource, you have to create a context.xml file inside META-INF directory inside your own application. It means, the datasource will be eligable only for the current application.

The content of the context.xml file should be anything like this:

<Context path="/DBTest" docBase="DBTest" debug="5" reloadable="true" crossContext="true">
     <Resource name="jdbc/TestDB"
                    auth="Container"type="javax.sql.DataSource"
                    maxActive="100"
                    maxIdle="30"
                    maxWait="10000"
                    username="username"
                    password="password"
                    driverClassName="driverClass"
                    url="URL"/>
</Context>

Besides it, you have to put the JARs files from your JDBC in the Tomcat’s classpath (not application’s classpath). It is also simple to do. Simply copy the required JAR files to apache-tomcat-5.5.25/common directory. Here there is a difference between Tomcat 5.5 and 6.x. In 6.x, the classpath directory is different. You have to copy the JARs to apache-tomcat-6.0/lib directory.

Setting up the web.xml file

Whatever application server you are working, you have to set up the web.xml file in the same way.

For our example, you have to add the following lines:

	<resource-ref>
		<res-ref-name>jdbc/TestDB</res-ref-name>
		<res-type>javax.sql.DataSource</res-type>
		<res-auth>Container</res-auth>
	</resource-ref>

Accessing the DataSource in Java

After all, you have to implement a class to access the DataSource.

As expected, the DataSource must be located using JNDI. Below following an example in Java.

 	try {
                  InitialContext initial = new InitialContext();
                  Context context = (Context) initial.lookup("java:/comp/env");
                  DataSource ds = (DataSource) context.lookup("jdbc/TestDB");
                  Connection con = ds.getConnection();
        } catch (SQLException e) {
                  e.printStackTrace();
        } catch (NamingException e) {
                  e.printStackTrace();
 	}

The code above gets a connection from DataSource configured in Tomcat and store it to a java.sql.Connection object.

In this way, you are able to work with DataSource in your application.

I hope this topic is useful for everyone.

If you have any feedback, fell free to make a comment.

CYA.

Installing and configurating Apache Tomcat 5.5 and 6.x. (Windows and Linux)

Downloading the proper version

Installing Tomcat

Windows Installation

Unix/Linux installation

Starting up, testing and shutting down

Tomcat Manager

Deploying an application without Tomcat Manager

Creating a DataSource in Apache Tomcat

Setting up the web.xml file

Jair Rillo Junior

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