Welcome!

Eclipse Authors: Pat Romanski, Elizabeth White, Liz McMillan, David H Deans, JP Morgenthal

Related Topics: Eclipse

Eclipse: Article

Creating Web Applications with the Eclipse Web Tools Project

Using open source to develop Web applications, EJBs, and Web services

The Web Tools Project (WTP) by the Eclipse Foundation is a set of open source tools that substantially reduce the time required for the development of Web applications, EJBs, and Web services. The WTP's current version is 0.7.1 and version 1.0 is coming later this year. The framework provides wizards and tools to create EJBs, Web components such as servlets and JSPs, and Web services using the Axis engine. It also provides source editors for HTML, JavaScript, CSS, JSP, SQL, XML, DTD, XSD, and WSDL; graphical editors for XSD, WSDL, J2EE project builders, models, and a J2EE navigator; a Web service wizard, explorer, and WS-I Test Tools; and database access, query tools, and models.

In this article I'll show you how to develop and deploy a JSP Web application with WTP in less than an hour. I'll also cover the creation and deployment of a basic servlet and editing JSP with WTP. Let's develop the WTP application together but, first, we need to install the following software:

  1. J2SE 5.0 JRE: http://java.sun.com/j2se
  2. Eclipse 3.1: www.eclipse.org
  3. WTP 0.7.1: www.eclipse.org/webtools
  4. Tomcat 5.0: http://jakarta.apache.org/tomcat/
  5. MySQL 4.0.25: www.mysql.com
  6. MySQL Connector/J Driver 3.1: www.mysql.com/products/connector/j/

Application Overview
Our application will be a basic Web application implementing the following use cases:

  • Customers need to register on the site to place orders.
  • Customers can place orders.
  • Customers can view their orders.
  • Admin can list all registered customers.

The system will be implemented using a servlet programming model and MySQL database.

Configuring MySQL Database and the Data Source
By default, when MySQL gets installed, a TEST database is available. Be sure to launch C:\Mysql\winmysqladmin.exe to specify the user name and password (the first time you launch it, it lets you do it and also starts the database server). It's necessary to copy MySQL Connector/J JDBC Driver: mysql-connector-java-3.1.10-bin.jar to the Tomcat/common/lib directory, so the Tomcat server can recognize it.

To configure MySQL database access in Tomcat, we have to add a separate file called Listing 1: DBTest.xml; the file follows a convention of "application_name.xml" under $TOMCAT\conf\catalina\localhost directory. The only problem with this file is that it may get deleted when the application is undeployed, so if you undeploy and redeploy the application, you have to place this file into the same folder again (so it's a good idea to save it somewhere else). Looking inside the DBTest.xml file, please note that in our case we are using "ODBC" for the username and don't provide any password.

Building Our Web Application Using Web Tools and a Database
Before we can start working on the Web project, we must configure Tomcat 5.0 in Eclipse to be our default server. When Web Tools are installed in Eclipse, new perspectives and options are added, such as a J2EE perspective where you can create J2EE projects, Web projects, and Web services. New options are available under the Window-Preferences menu for configuring Tomcat servers with Eclipse. Go to Window - Preferences menu, under Server select - Installed Runtimes, click Add, and then specify Tomcat 5.0 server with the installed JRE and a path to the Tomcat installation directory (see Figure 1). Now create a Dynamic Web Project using the Web Tools wizard by selecting File-New-Other, then expanding Web-Dynamic Web Project.

We'll name the project DBTest, which will also become its context root. The Web module will be targeted to our default server: Tomcat. Click Finish and the DBTest Web project gets created. This project will contain all of our Web resources, such as HTML and JSP files, and servlets, and you'll be able to export it into a standard WAR file later, if needed.

Creating Supporting Domain Classes and Tables
Before creating servlets, let's create supporting classes to represent a customer and an order. The class diagram in Figure 2 depicts the Customer and Order relationship.

Note that when creating Customer and Order classes, we define corresponding fields as their public instance variables and then can automatically generate getters and setters from those fields. This can be easily done by going to Outline view (appears after you double-click on an existing class name or create a new class), selecting a class, and selecting "Source - Generate Getters and Setters..." from the right-button menu (see Figure 3).

Along with the classes, we'd have to create corresponding database tables in a MySQL database:


CREATE TABLE CUSTOMER (
ID INT PRIMARY KEY,
FIRST_NAME VARCHAR(50),
LAST_NAME VARCHAR(50),
ADDRESS VARCHAR(150));

CREATE TABLE ORDERS (
ID INT PRIMARY KEY,
CUST_ID INT REFERENCES CUSTOMER,
DATE_PLACED DATE,
AMOUNT INT);

Creating Database Command Classes
We'll create a special package with classes that implement a Command design pattern to perform necessary database updates. The Command pattern allows the classes to implement the common interface executing some particular command. Examples of the Command pattern in Java would be classes that implement the ActionListener interface with the actionPerformed() method. Our Command pattern interface for database integration is presented in Listing 2.

Classes implementing this command will be performing the actual database operations for reading and inserting rows into customer and order tables. The following use cases will be addressed:

  • Customers want to register on the site in order to place orders (a new row is created in the customer table)
  • Customers can place the order (the order gets created in the database for a particular customer)
  • Customers can view the orders they have placed
  • Admin can list all the customers

Based on these use cases, the following classes have implemented the DatabaseCommand interface (see Listings 3-6):

public class CreateCustomer implements DatabaseCommand
public class CreateOrder implements DatabaseCommand
public class ListCustomers implements DatabaseCommand
public class ListCustomerOrders implements DatabaseCommand

Finally, in order to execute our command classes, we will need to create a class that would access the database datasource, obtain a SQL connection, and then execute a particular database command. This class will implement a Singleton design pattern, which we'll call CommandExecutor:

Object o = CommandExecutor.getInstance().executeDatabaseCommand
(<<instance of the particular database command class goes here>>).

The CommandExecutor class will perform the datasource lookup as follows:

InitialContext ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup("java:comp/env");
ds = (DataSource) envCtx.lookup("jdbc/TestDB");

This finds the reference to the data-source we have defined in DBTest.xml by resolving its reference in a Web deployment descriptor (web.xml), which we'll define in a section below. Listing 7 has the complete code of the Command Executor class.

More Stories By Boris Minkin

Boris Minkin is a Senior Technical Architect of a major financial corporation. He has more than 15 years of experience working in various areas of information technology and financial services. Boris is currently pursuing his Masters degree at Stevens Institute of Technology, New Jersey. His professional interests are in the Internet technology, service-oriented architecture, enterprise application architecture, multi-platform distributed applications, and relational database design. You can contact Boris at [email protected]

Comments (15)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Digital Transformation is much more than a buzzword. The radical shift to digital mechanisms for almost every process is evident across all industries and verticals. This is often especially true in financial services, where the legacy environment is many times unable to keep up with the rapidly shifting demands of the consumer. The constant pressure to provide complete, omnichannel delivery of customer-facing solutions to meet both regulatory and customer demands is putting enormous pressure on...
IoT is rapidly becoming mainstream as more and more investments are made into the platforms and technology. As this movement continues to expand and gain momentum it creates a massive wall of noise that can be difficult to sift through. Unfortunately, this inevitably makes IoT less approachable for people to get started with and can hamper efforts to integrate this key technology into your own portfolio. There are so many connected products already in place today with many hundreds more on the h...
The standardization of container runtimes and images has sparked the creation of an almost overwhelming number of new open source projects that build on and otherwise work with these specifications. Of course, there's Kubernetes, which orchestrates and manages collections of containers. It was one of the first and best-known examples of projects that make containers truly useful for production use. However, more recently, the container ecosystem has truly exploded. A service mesh like Istio addr...
Digital Transformation: Preparing Cloud & IoT Security for the Age of Artificial Intelligence. As automation and artificial intelligence (AI) power solution development and delivery, many businesses need to build backend cloud capabilities. Well-poised organizations, marketing smart devices with AI and BlockChain capabilities prepare to refine compliance and regulatory capabilities in 2018. Volumes of health, financial, technical and privacy data, along with tightening compliance requirements by...
Charles Araujo is an industry analyst, internationally recognized authority on the Digital Enterprise and author of The Quantum Age of IT: Why Everything You Know About IT is About to Change. As Principal Analyst with Intellyx, he writes, speaks and advises organizations on how to navigate through this time of disruption. He is also the founder of The Institute for Digital Transformation and a sought after keynote speaker. He has been a regular contributor to both InformationWeek and CIO Insight...
Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settlement products to hedge funds and investment banks. After, he co-founded a revenue cycle management company where he learned about Bitcoin and eventually Ethereal. Andrew's role at ConsenSys Enterprise is a mul...
To Really Work for Enterprises, MultiCloud Adoption Requires Far Better and Inclusive Cloud Monitoring and Cost Management … But How? Overwhelmingly, even as enterprises have adopted cloud computing and are expanding to multi-cloud computing, IT leaders remain concerned about how to monitor, manage and control costs across hybrid and multi-cloud deployments. It’s clear that traditional IT monitoring and management approaches, designed after all for on-premises data centers, are falling short in ...
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
Dynatrace is an application performance management software company with products for the information technology departments and digital business owners of medium and large businesses. Building the Future of Monitoring with Artificial Intelligence. Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more busine...