java left logo
java middle logo
java right logo
 


 
 
Main Menu
Home
Java Tutorials
Book Reviews
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Java Network
Java Forums
Java Blog




Most Visited Tips
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Book Reviews
Top Rated Tips
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Book Reviews


Statistics
Registered Users: 4093
Java SE Tips: 614
Java ME Tips: 202
Java EE Tips: 183
Other API Tips: 779
Java Applications: 298
Java Libraries: 209
Java Games: 16
Book Reviews:
 
 
 
Introduction to Java Servlets with NetBeans E-mail
User Rating: / 644
PoorBest 

Implementation of Tutorial’s Example

For our tutorial, we are going to use index.jsp to demonstrate how to implement Java Servlet that greets the users. Index.jsp will be used to obtain the first name as well as the last name / surname of the users. For this case, textboxes should be adequate as first name and surname. However, it would be different case if we are required to get the country of origin of the users. The use of combobox would be more appropriate for choosing the country of origin as there are more than one choices to be chosen on. We are also required to create one more JSP file called greeting.jsp to greet the users. Hence, the flow would be index.jsp - GreetingServlet -> greeting.jsp. In short, index.jsp will first be displayed to users, the users then fill his or her first and surname in index.jsp and press Submit button. This information is sent to our Java Servlet and our Java Servlet redirects the users to the greeting.jsp.

In index.jsp, we need to have two textboxes for getting the user’s input and a button to submit the information to our Java Servlet. After pressing the button, the user should be redirected into greeting page. Now, let’s create the textbox. The textbox command would be the same as HTML command that is <input type=”text” value=”50”> and so on. Please remember that every textbox or components whose values would like to be passed into Java Servlet must be within <form></form> tag. Thus, please add below lines of codes into your index.jsp after the <h1></h1> tag.</p>

    <form action="GreetingServlet" method="POST">
        First Name: <input type="text" name="firstName" size="20"><br />
        Surname: <input type="text" name="surname" size="20">
        <br /><br />
        <input type="submit" value="Submit">
    </form>

Now, we have <form> and </form> HTML tag. Inside <form></form> tag, we need to specify few values such as action and method. Action is used to allow the JSP page knows which Java Servlet to be called on the invocation of submit button and the method is used to select the preferred way to pass your information to Java Servlet. This method attribute will be discussed further in the later phase.

We also have two textboxes now i.e <input type="text" name="firstName" size="20"> and <input type="text" name="surname" size="20">. There are few important things that you need to pay attention here. The name attribute for these textbox component are extremely important; in our index.jsp, it would be firstName and surname. These keywords are used to obtain the information in Java Servlet from the JSP page. It would be demonstrated in later phase once you have seen the implementation of the Java Servlet. The type is used to define what kind of component it is; text represents textboxes, button represents a button, image represents a picture and etc. The size is used to determine the width of the textbox. For more information, you can reference to the HTML tag which is available in Internet.

Okay, you must be wondering how the index.jsp looks like now when it has been executed. Let’s deploy our JSP into the bundled Tomcat in NetBeans. Right-click your Web Application Project and choose Run Project. This menu first compiles and deploys the application to the Server and subsequently runs the application by executing its index.jsp. Yes, that is correct; it is just one click to run your Web Application within the NetBeans. Later on, if you have modified your JSP or your Java Servlet, you can merely re-deploy the application and all the changes will be reflected. You also need to refresh your Internet Browser.



Image

While running your Web Application Project, you may be prompted with a dialog box showing the progress of your Web Application project. If you carefully pay attention on the dialog box, they once display the message like “Starting Tomcat 5.5.7” and etc. Wait for a few seconds and your default Internet Browser will be launched and it should display your new index.jsp.

Below screenshot shows how the index.jsp should look like.



Image

We have completed our index.jsp. What we need to do now is to create our Java Servlet which is called GreetingServlet. Actually, the name of the Java Servlet can be anything as you want. The most important thing is how you map this Java Servlet in your web.xml to be accessible from your JSP. Well, web.xml is actually a deployment descriptor and it must always be present for each Java J2EE Web Application. For now, what you need to know is that every Java Servlet that you create must be registered in the web.xml file. Thus, this file may be getting bigger and bigger if the project is getting more complex. This will be described in the next phase.

To create your Java Servlet, you need to right-click your Source Packages section within your Web Application and choose New > Servlet as shown on below figures.



Image

Image

Again, a wizard should pop up for you to configure your Java Servlet. Your Java Servlet name can be anything but for this tutorial sample, let’s name it GreetingServlet. If you want the Java Servlet to be on different name, you need to modify the mapping of your web.xml as well. This web.xml will be discussed in later phase. For now, we can keep the location be in the Source Packages. This Source Packages should only contain Java files. The reason we have this Source Packages is to assist us in maintaining our Web Application. Consider that if you have all the JSP, Java and other files in one folder, it would be hard for you or the new developers to track the flow of the applications.

For the Package, you can define any package that you want. Normally, we use Package to group a few Java files that has the same functionalities. For example, if I have StringUtil.java for String manipulation and EncodingAlgorithmUtil.java for encoding, I will locate them under the same package called “com.mycompanyname.util” as they both are actually utility classes. So as this is our first Java Servlet, let’s create one package called “com.mycompany.servlet”. Then press Next button.



 
< Prev
Posted by S.Ramkumar, on Tuesday, 06 June 2006 at 2:00

Excellent topic included with Netbean 5.0 editor


Posted by Rhys Campbell, on Monday, 05 June 2006 at 11:40

Thanks, simple but effective!


 1 
Page 1 of 1 ( 2 comments )

You can share your information about this topic using the form below!

Please do not post your questions with this form! Thanks.


Name (required)


E-Mail (required)

Your email will not be displayed on the site - only to our administrator
Homepage(optional)



Comment Enable HTML code : Yes No



 
       
         
     
 
 
 
   
 
 
java bottom left
java bottom middle
java bottom right
RSS 0.91 FeedRSS 1.0 FeedRSS 2.0 FeedATOM FeedOPML Feed

Home - About Us - Privacy Policy
Copyright 2005 - 2008 www.java-tips.org
Java is a trademark of Sun Microsystems, Inc.