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Connecting Tomcat 7 Web Application to Database Using JNDI

Several weeks ago, I looked at the some decompiled Java codes from a fairly small web application that basically records cheque numbers and generates reports.  To my surprise, it was written in dreadful codes full of clutter and signs of haste! I almost cried. Just imagine the following code littered all around the application and entangled by a lot of package-level instance variables. Not to mention the SQL-statements-in-Servlets type of design pattern.

Thus, this blog.

This is how I do things.

Software Applications used

  1. Tomcat 7.0.23
  2. JDK1.6
  3. Eclipse
  4. HSQL 2.2.6

Step 1 – Download and set up HSQL Database

Please see Tomcat 7 and Up: JDBC Realm on how to create a database and start the HSQL server. For this blog, we will use

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Create table and insert sample data

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Test Data

Step 2– Create an Eclipse project and Servlet that uses our database.

The workspace.

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Java project in Eclipse

The Servlet code

WARNING: This is just for demonstration purposes. Do not put SQLs in your Servlets.

The web.xml

The web applicaiton directory structure and the required HSQL jar file.

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The Web App dir and required HSQL jar file

Step 3 – Configure Tomcat7

a) Add the following between the context tags in <TOMCAT_HOME>/conf/context.xml

Step 4 – Start Tomcat and Test the web application

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And you are done!