Feb 17, 2019 In this tutorial I show you how to install Apache Tomcat, Java, and Eclipse on Windows and MacOS. MacOS users skip to 6:49. Along with that we'll run a Java Server Page and Servlet. Tomcat Controller is a simple system preference pane to start and stop the Apache Tomcat server put out by the Jakarta group. You may want to check out more Mac applications, such as Draft Control, BitNami Stack for Tomcat or Music Control for iTunes, Spotify, Rdio and Personalized Internet Radio, which might be related to Tomcat Controller. Installing Tomcat 9 on Mac OS X El Capitan is actually quite easy. The Mac OS X installation process is fairly painless and straight forward, but there are a few rough spots along the way. Follow these step by step instructions to get Tomcat up and running on your Mac OS X machine in no time. Tomcat 8.5.23 - Java Servlet Internet server. Download the latest versions of the best Mac apps at safe and trusted MacUpdate.
This practical can be completed in a 3-hour session.
This installation and configuration guide is applicable to Tomcat 9, and possibly the earlier versions. Take note that Tomcat 9 requires JDK 8 and later.
Tomcat is the servlet container that is used in the official Reference Implementation for the Java Servlet and JavaServer Pages technologies. The Java Servlet and JavaServer Pages specifications are developed by Sun under the Java Community Process. Tomcat is developed in an open and participatory environment and released under the Apache Software License.
IntroductionWeb Application (Webapp)![]()
A web application (or webapp), unlike standalone application, runs over the Internet. Examples of webapps are google, amazon, facebook and twitter.
A webapp is typically a 3-tier (or multi-tier) client-server database application run over the Internet as illustrated in the diagram below. It comprises five components:
A typical use case is:
Hypertext Transfer Protocol (HTTP)
Apache Tomcat HTTP Server
Apache Tomcat is a Java-capable HTTP server, which could execute special Java programs known as 'Java Servlet' and 'Java Server Pages (JSP)'. Tomcat is an open-source project, under the 'Apache Software Foundation' (which also provides the most use, open-source, industrial-strength Apache HTTP Server). The mother site for Tomcat is http://tomcat.apache.org. Alternatively, you can find tomcat via the Apache mother site @ http://www.apache.org.
Tomcat was originally written by James Duncan Davison (then working in Sun) in 1998, based on an earlier Sun's server called Java Web Server (JWS). It began at version 3.0 after JWS 2.1 it replaced. Sun subsequently made Tomcat open-source and gave it to Apache.
The various Tomcat releases are:
How to Install Tomcat and Get Started with Java Servlet ProgrammingSTEP 0: Create a Directory to Keep all your Works
I shall assume that you have created a directory called '
c:myWebProject ' (for Windows) or '~myWebProject ' (for Mac OS X) in your earlier exercises. Do it otherwise. This step is important; otherwise, you will be out-of-sync with this article and will not be able to find your files later.
STEP 1: Download and Install Tomcat
For Windows
Take note of Your Tomcat Installed Directory. Hereafter, I shall refer to the Tomcat installed directory as
<TOMCAT_HOME> .
For Mac OS X
Take note of Your Tomcat Installed Directory. Hereafter, I shall refer to the Tomcat installed directory as
<TOMCAT_HOME> .
For Ubuntu
Read 'How to Install Tomcat on Ubuntu'. You need to switch between these two articles.
For academic learning, I recommend '
zip ' (or 'tar.gz ') package, as you could simply delete the entire directory when Tomcat is no longer needed (without running any un-installer). You are free to move or rename the Tomcat's installed directory. You can install (unzip) multiple copies of Tomcat in the same machine.
Tomcat's Sub-Directories
Take a quick look at the Tomcat installed directory. It contains the these sub-directories:
STEP 2: Create an Environment Variable JAVA_HOME
(For Windows)
You need to create an environment variable (system variable available to all applications) called '
JAVA_HOME ', and set it to your JDK installed directory.
Follow the steps HERE!
(For Mac OS)
Skip this step. No need to do anything.
STEP 3: Configure the Tomcat Server
The Tomcat configuration files, in XML format, are located in the '
conf ' sub-directory of your Tomcat installed directory, e.g. 'c:myWebProjecttomcatconf ' (for Windows) or '~/myWebProject/tomcat/conf ' (for Mac OS X). The important configuration files are:
Make a BACKUP of the configuration files before you proceed!!!
Step 3(a) 'confserver.xml' - Set the TCP Port Number
Use a programming text editor (e.g., Sublime Text, Atom) to open the configuration file '
server.xml '.
The default TCP port number configured in Tomcat is 8080, you may choose any number between 1024 and 65535, which is not used by existing applications. We shall choose 9999 in this article. (For production server, you should use port 80, which is pre-assigned to HTTP server as the default port number.)
Locate the following lines (around Line 69) that define the HTTP connector, and change
port='8080' to port='9999' .
Step 3(b) 'confweb.xml' - Enable Directory Listing
Again, use a programming text editor to open the configuration file '
web.xml '.
We shall enable directory listing by changing '
listings ' from 'false ' to 'true ' for the 'default ' servlet. This is handy for test system, but not for production system for security.
Locate the following lines (around Line 108) that define the '
default ' servlet; and change the 'listings ' from 'false ' to 'true '.
Step 3(c) 'confcontext.xml' - Enabling Automatic Reload
We shall add the attribute
reloadable='true' to the <Context> element to enable automatic reload after code changes. Again, this is handy for test system but not recommended for production, due to the overhead of detecting changes.
Locate the
<Context> start element (around Line 19), and change it to <Context reloadable='true'> .
STEP 4: Start Tomcat Server
The Tomcat's executable programs and scripts are kept in the '
bin ' sub-directory of the Tomcat installed directory.
Step 4(a) Start Server
For Windows
I shall assume that Tomcat is installed in '
c:myWebProjecttomcat '. Launch a CMD shell and issue:
For Mac OS
I assume that Tomcat is installed in '
~/myWebProject/tomcat '. To start the Tomcat server, open a new 'Terminal' and issue:
A new Tomcat console window appears (with Java's coffee-cup logo as icon). Study the messages on the console. Look out for the Tomcat's port number. Double check that Tomcat is running on port 9999 as configured.
Error messages will be sent to this console.
System.out.println() issued by your Java servlets will also be sent to this console.
(Skip Unless ..) Cannot Start Tomcat: Read 'How to Debug'.
Step 4(b) Start a Client to Access the Server
Start a browser (Firefox, Chrome) as an HTTP client. Issue URL '
http://localhost:9999 ' to access the Tomcat server's welcome page. The hostname 'localhost ' (with IP address of 127.0.0.1 ) is meant for local loop-back testing within the same machine. For users on the other machines over the net, they have to use the server's IP address or DNS domain name in the form of 'http://serverHostnameOrIPAddress:9999 '.
(Optional) Try issuing URL
http://localhost:9999/examples to view the servlet and JSP examples. Try running some of the servlet examples.
Step 4(c) Shutdown Server
For Windows
You can shutdown the tomcat server by either:
For Mac OS
To shutdown the Tomcat server:
WARNING: You MUST properly shutdown the Tomcat. DO NOT kill the CAT by pushing the window's 'CLOSE' button.
STEP 5: Develop and Deploy a WebAppStep 5(a) Create the Directory Structure for your WebApp
Let's call our first webapp '
hello '. Goto Tomcat's 'webapps ' sub-directory and create the following directory structure for your webapp 'hello ' (as illustrated): https://hrrenew267.weebly.com/blog/solid-works-for-mac.
You need to keep your web resources (e.g., HTMLs, CSSs, images, scripts, servlets, JSPs) in the proper directories:
You should RE-START your Tomcat server to pick up the
hello webapp. Check the Tomcat's console to confirm that 'hello ' application has been properly deployed:
You can issue the following URL to access the web application '
hello ':
You should see the directory listing of the directory '
<TOMCAT_HOME>webappshello ', which shall be empty at this point of time. Take note that we have earlier enabled directory listing in 'web.xml '. Otherwise, you will get an error '404 Not Found'.
Step 5(b) Write a Welcome Page
Create the following HTML page and save as '
HelloHome.html ' in your webapp's root directory 'hello '.
You can browse this page by issuing this URL:
Alternatively, you can issue an URL to your webapp's root '
hello ':
The server will return the directory listing of your base directory. You can then click on '
HelloHome.html '.
Rename '
HelloHome.html ' to 'index.html ', and issue a directory request again:
Now, the server will redirect the directory request to '
index.html ', if the root directory contains an 'index.html ', instead of serving the directory listing.
You can check out the home page of your peers by issuing:
with a valid ' YourPeerHostnameOrIPAddr ', provided that your peer has started his tomcat server and his firewall does not block your access. You can use command such as 'ipconfig ' (Windows), 'ifconfig ' (Mac OS X and Unix) to find your IP address.
(Skip Unless..) The likely errors are 'Unable to Connect', 'Internet Explorer cannot display the web page', and '404 File Not Found'. Read 'How to Debug' section.
STEP 6: Write a 'Hello-world' Java Servlet
A servlet is Java program that runs inside a Java-capable HTTP Server, such as Apache Tomcat. A web user invokes a servlet by issuing an appropriate URL from a web browser (HTTP client).
Before you proceed, I shall assume that you are familiar with Java Programming and have installed the followings:
Step 6(a) Write a 'Hello-world' Java Servlet
A Java servlet is a Java program that runs inside a HTTP server. A web user invokes a servlet by issuing a URL from a browser (or HTTP client).
In this example, we are going to write a Java servlet called
HelloServlet , which says 'Hello, world!'. We will configure such that web users can invoke this servlet by issuing URL http://ip_addr:port/hello/sayhello from their browser, as illustrated:
Write the following source codes called '
HelloServlet.java ' and save it under your application 'classes ' directory (i.e., '<TOMCAT_HOME>webappshelloWEB-INFclassesHelloServlet.java '). This servlet says 'Hello', echoes some request information, and prints a random number upon each request.
Take note that in Line 7, we configure this
HelloServlet to URL '/sayhello ' via annotation @WebServlet('/sayhello') , which is applicable to Tomcat 7 onwards. In other words, the full URL shall be http://ip_addr:port/hello/sayhello to trigger this HelloServlet .
Step 6(b) Compiling the Servlet (DIFFICULT)
We need the Java Servlet API to compile the servlet. Servlet API is NOT part of JDK. Tomcat provides a copy in
<TOMCAT_HOME>/lib/servlet-api.jar . We need to include this JAR file in the compilation via the -cp (classpath) option as follows:
(For Mac OS)
The output of the compilation is '
HelloServlet.class '.
Use your 'File Explorer' to check the '
webapps/hello/WEB-INF/classes ' folder to make sure that 'HelloServlet.class ' has been created in the right place.
Step 6(c) Invoke the Servlet
Restart your Tomcat Server (just in case ..).
To invoke this servlet, start a browser, and issue the request URL configured as follows:
You shall see the output of the servlet displayed in your web browser.
Refresh the browser, you shall see a new random number upon each refresh. In other word, the
doGet() method of the servlet runs once per request.
View Page Source
(For Firefox and Chrome) Right-click the page ⇒ 'View Page Source' to look at the output received by the web browser (which is returned by the server). Take note that the web browser receives only the output of the servlet (generated via the
out.println() statements). The client has no access to the servlet source codes (which may contain confidential information).
(For Mac OS's Safari browser) You need to enable 'Developer Menu' under the 'Preferences' to enable the 'View Source' menu.
(Skip Unless..) The likely errors are '404 File Not Found' and '500 Internal Server Error'. Read 'How to debug' Section.
(Optional) Inspecting HTTP Request and Response Messages
When you enter a URL (e.g.,
http://localhost:9999/hello/sayhello ) on a web browser, an HTTP GET request message is sent to the server; and the server returns a response message for display on the web browser. You can inspect the request and response messages via Web browser's Developer Tool.
For Firefox/Chrome, press F12 (called F12 debugger) to enable 'Web Console' or 'Developer Tool'. Choose 'Console' or 'Network' pane. Enter URL
http://localhost:9999/hello/sayhello (or refresh). Enable 'Net' (not in Gray). Expand the link http://localhost:9999/hello/sayhello . A HTTP message consists of a header and a body. Inspect the request header and body; as well as the response header and body.
The request message header is as follows:
For this request, there is no request message body.
The response message header is as follows:
The response message body is as follows:
STEP 7: Write a Database Servlet
This section assumes that you are familiar with 'Java database programming' and 'MySQL database server'. Otherwise, read 'Java Database Program' and 'How to Install MySQL and Get Started', respectively.
Step 7(a) Setup a Database on MySQL (Already done in the MySQL exercises)
Start your MySQL server. Take note of the server's port number. Toby mac burning for you. I shall assume that the MySQL server is running on port
3306 , whereas the Tomcat is running on port 9999 .
Start a MySQL client. I shall assume that there is a user called '
myuser ' with password 'xxxx '.
Run the following SQL statements to create a database called '
ebookshop ', with a table called 'books ' with 5 columns: id , title , author , price , qty .
Step 7(b) Install MySQL JDBC Driver (Already done in the previous JDBC exercises)
You need to download MySQL JDBC driver if you have not done so. Read 'Installing the MySQL JDBC Driver'.
Step 7(c) Copy the MySQL JDBC Drive to Tomcat's 'lib' (IMPORTANT!!!)![]()
Copy the MySQL JDBC Driver
JAR file 'mysql-connector-java-8.0.{xx}.jar ' into Tomcat's lib directory, i.e., 'c:myWebProjecttomcatlib ' (for Windows) or '~myWebProjecttomcatlib ' (Mac OS).
Step 7(d) Write a Client-side HTML Form
Let's write an HTML script to create a query form with 3 checkboxes and a submit button, as illustrated below. Save the HTML file as “ querybook.html ” in your application root directory “<TOMCAT_HOME>webappshello ”.
You can browse the HTML page by issuing the following URL:
Check a box (e.g., 'Tan Ah Teck') and click the 'Search' button. You are expected to get an error '404 File Not Found', as you have yet to write the server-side program.
But observe the URL in the browser's navigation bar, reproduced as follows:
The URL request consists of two part: a URL corresponding to the '
action ' attribute of the <form> tag, and the 'name=value' pair extracted from the <input> tag, separated by a '?' . Take note that blanks are replaced by '+' (or %20 ), because blanks are not allowed in the URL.
If you check two boxes (e.g., 'Tan Ah Teck' and 'Mohammad Ali'), you will get this URL, which has two 'name=value' pairs separated by an
'&' .
Step 7(e) Write the Server-side Database Query Servlet
The next step is to write a Java servlet, which responses to the client’s request by querying the database and returns the query results. Google drive for mac os catalina.
Take note that in Line 8, we configure this
QueryServlet to URL '/query ' via annotation @WebServlet('/query') . In other words, the full URL to trigger this QueryServlet is http://ip_addr:port/hello/query , which corresponds to the 'action ' attribute of the <form> tag of the 'querybook.html ' written earlier.
Compile '
QueryServlet.java ' as follows:
Use a 'File Explorer', verify that '
QueryServlet.class ' was generated in the 'classes ' directory.
Step 7(f) Invoke the Servlet from the Client-Side Form
Issue the following URL to browse the HMTL form '
querybook.html ' that you have created earlier:
Select an author (e.g., 'Tan Ah Teck') and click the submit button, which activates the following URL coded in the
<form> 's 'action ' attribute, together with the name=value pair:
This URL '/
query ' triggers QueryServlet . The QueryServlet retrieves the name=value pair of 'author=Tan+Ah+Teck '. Inside the QueryServlet , the method request.getParameter('author') returns 'Tan Ah Teck ', which is inserted into the SQL SELECT command to query the database. The processed query result is then written to the client as an HTML document.
(Skip Unless..) If you see a blank screen or incorrect output, look for error messages from the Tomcat console!!! Check 'How to debug' Database Servlet Errors.
(Archive)(Prior to Tomcat 7) Deploying Servlets using web.xml
Please skip this section. I keep it here just in case..
The annotation
@WebServlet('url') for deploying servlet is supported from Tomcat 7/Servlet 3.0. Prior to Tomcat 7, you need to deploy servlets via deployment descriptors in the web.xml configuration file.
Create the following configuration file called '
web.xml ', and save it under 'webappshelloWEB-INF ' (i.e., '<TOMCAT_HOME>webappshelloWEB-INFweb.xml ').
In the above configuration, a servlet having a class file '
HelloServlet.class ' is mapped to request URL '/sayhello ' (via an arbitraryservlet-name 'HelloWorld '), under this web application 'hello '. In other words, the complete request URL for this servlet is 'http://hostname:port/hello/sayhello '.
This configuration file, saved under your webapp '
hello ', is applicable only to this particular webapp 'hello '.
Restart your Tomcat server to refresh the '
web.xml ' file.
Note: For EACH servlet, you need to write a pair of
<servlet> and <servlet-mapping> elements with a common but arbitrary <servlet-name> . Take note that all the <servlet> elements MUST be grouped together and placed IN FRONT of the <servlet-mapping> elements.
(Skip Unless..) How to Debug?
'Everything that can possibly go wrong will go wrong.' The most important thing to do is to find the ERROR MESSAGES!!!
Always..
Install Tomcat On MacCannot Start Tomcat after InstallationApache Tomcat For MacLocating/Killing Tomcat's Process
Cannot Access the Tomcat Server From BrowserJava Servlet ErrorsJava Database Servlet Errors
REFERENCES & RESOURCES
ContentTomcat Native Downloads
Use the links below to download the Apache Tomcat® Native software from one of our mirrors. You mustverify the integrity of the downloaded files using signatures downloaded from our main distribution directory.
Only current recommended releases are available on the main distribution site and its mirrors. Older releases are available from the archive download site.
Recent releases (48 hours) may not yet be available from the mirrors.
Choose a Mirror
You are currently using http://ftp.fau.de/apache/. If you encounter a problem with this mirror, please select another mirror. If all mirrors are failing, there are backup mirrors (at the end of the mirrors list) that should be available.
You may also consult the complete list of mirrors.
Tomcat Native Connector - 1.2Download Tomcat For Mac
For more information concerning Tomcat Native, see the Tomcat Native site.
Tomcat 9 For Mac
You can find binaries release too. You may download them from HERE
Verify the Integrity of the Files
You mustverify the integrity of the downloaded files. We provide OpenPGP signatures for every release file. This signature should be matched against the KEYS file which contains the OpenPGP keys of Tomcat's Release Managers. We also provide
SHA512 checksums for every release file. After you download the file, you should calculate a checksum for your download, and make sure it is the same as ours.
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