Java Practical info : Session Tracking

Servlet Error Handling

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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                                         Hi All
Everyone is enjoyed Christmas festival still some part of the world celebration
going up to New Year. Any have spent some valuable time to see my blog also for
this thanks lot. I am trying to give some information regarding Servlet
Exception Handling. In Every Application Development you must raise some un
excepted error may occurred. Sometimes you need to handle Exception for end
user point of you, so in order to use servlet you need to handle exception in
the following different ways. Any one of the technique you can implement some
times more than one technique also allows.  Now the time to see the different Techniques.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">When a servlet throws an exception, the web
container searches the configurations in web.xml that use the <b>exception-type</b>
element for a match with the thrown exception type.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">You would have to use the error-page element in web.xml to specify the invocation
of servlets in response to certain exceptions or HTTP status codes.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Consider, you have an ErrorHandler servelt which would be called whenever there
is any defined exception or error. Following would be the entry created in <b>web</b>.xml.<o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><servlet><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">       
<servlet-name>ErrorHandler</servlet-name><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">       
<servlet-class>ErrorHandler</servlet-class><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></servlet><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><servlet-mapping><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">       
<servlet-name>ErrorHandler</servlet-name><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">       
<url-pattern>/ErrorHandler</url-pattern><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></servlet-mapping><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<error-code>404</error-code><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<location>/ErrorHandler</location><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<error-code>403</error-code><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<location>/ErrorHandler</location><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">    <exception-type><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">         
javax.servlet.ServletException<o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">    </exception-type ><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<location>/ErrorHandler</location><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"><error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<exception-type>java.io.IOException</exception-type ><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">   
<location>/ErrorHandler</location><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;"></error-page><o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt; line-height: 115%;">2.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: Georgia, serif; font-size: 12pt; line-height: 115%;">If you want to have a generic
Error Handler for all the exceptions then you should define following
error-page instead of defining separate <b>error-page</b>
elements for every exception:</span><o:p></o:p></div>
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<pre style="background: #F1F1F1;"><span style="font-family: Georgia, serif; font-size: 12pt;"><error-page><o:p></o:p></span></pre>
<pre style="background: #F1F1F1;"><span style="font-family: Georgia, serif; font-size: 12pt;">    <exception-type>java.lang.Throwable</exception-type ><o:p></o:p></span></pre>
<pre style="background: #F1F1F1;"><span style="font-family: Georgia, serif; font-size: 12pt;">    <location>/ErrorHandler</location><o:p></o:p></span></pre>
<pre style="background: #F1F1F1;"><span style="font-family: Georgia, serif; font-size: 12pt;"></error-page><o:p></o:p></span></pre>
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<span style="font-family: Georgia, serif; font-size: 12pt;">Following are the points to be
noted about above web.xml for Exception Handling:<o:p></o:p></span></div>
<ul type="disc">
<li class="MsoNormal" style="background-color: white; background-position: initial initial; background-repeat: initial initial; text-align: justify;"><span style="font-family: "Georgia","serif"; font-size: 12.0pt; mso-bidi-font-family: "Courier New"; mso-fareast-font-family: "Times New Roman";">The servelt ErrorHandler is defined in
     usual way as any other servlet and configured in web.xml.<o:p></o:p></span></li>
<li class="MsoNormal" style="background-color: white; background-position: initial initial; background-repeat: initial initial; text-align: justify;"><span style="font-family: "Georgia","serif"; font-size: 12.0pt; mso-bidi-font-family: "Courier New"; mso-fareast-font-family: "Times New Roman";">If there is any error with status code
     either 404 ( Not Found) or 403 ( Forbidden ), then ErrorHandler servlet
     would be called.<o:p></o:p></span></li>
<li class="MsoNormal" style="background-color: white; background-position: initial initial; background-repeat: initial initial; text-align: justify;"><span style="font-family: "Georgia","serif"; font-size: 12.0pt; mso-bidi-font-family: "Courier New"; mso-fareast-font-family: "Times New Roman";">If the web application throws either ServletException or IOException,
     then the web container invokes the /ErrorHandler servlet.<o:p></o:p></span></li>
<li class="MsoNormal" style="background-color: white; background-position: initial initial; background-repeat: initial initial; text-align: justify;"><span style="font-family: "Georgia","serif"; font-size: 12.0pt; mso-bidi-font-family: "Courier New"; mso-fareast-font-family: "Times New Roman";">You can define different Error
     Handlers to handle different type of errors or exceptions. Above example
     is very much generic and hope it serve the purpose to explain you the
     basic concept.<o:p></o:p></span></li>
</ul>
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<span style="font-family: Georgia, serif; font-size: 12pt;">3.<span style="font-family: 'Times New Roman'; font-size: 7pt;">      </span></span><b><span style="font-family: Georgia, serif; font-size: 12pt;">Request Attributes - Errors/Exceptions</span></b><span style="font-family: Georgia, serif; font-size: 12pt;">:<o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt;">Following is the list of request
attributes that an error-handling servlet can access to analyses the nature of
error/exception.<o:p></o:p></span></div>
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<span style="font-family: Georgia, serif; font-size: 12pt; line-height: 115%;">Hey common I am not forced to
read entire thing here you know my motive right I am stopping here to give much
please see the following video you can understand better way .<o:p></o:p></span><br />
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<iframe allowfullscreen="allowfullscreen" frameborder="0" height="266" mozallowfullscreen="mozallowfullscreen" src="https://www.youtube.com/embed/vvr9i6uCeyc?feature=player_embedded" webkitallowfullscreen="webkitallowfullscreen" width="320"></iframe></div>
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Servlet Error Handling

Hi All Everyone is enjoyed Christmas festival still some part of the world celebration going up ...

Inter Servlet Communication?

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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjZN9ODO-_GLCR8RXHzwvD1a7_cad-ldzn6swpSAKK80VkoMcYoF4VHZAXagwho0I2M-V051wCp8TpmZBcN7WebqLkzh7sG5cdUAP9YsQX9v6xjNBBvD81LEjDC_l_AgXl5HulJ2PkQ92E/s1600/ctree.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjZN9ODO-_GLCR8RXHzwvD1a7_cad-ldzn6swpSAKK80VkoMcYoF4VHZAXagwho0I2M-V051wCp8TpmZBcN7WebqLkzh7sG5cdUAP9YsQX9v6xjNBBvD81LEjDC_l_AgXl5HulJ2PkQ92E/s1600/ctree.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Image Source  Google Images <b>Happy Christmas</b></td></tr>
</tbody></table>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                        Hi All my blog viewers Happy Christmas. To my post concentrating
on inter servlet communication.Before going to to how it works inter servlet
communication. Some of the important points you need to know.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Servlet Context<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">2.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Request Dispatcher Object.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><b><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Servlet
Context</span></b><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">: -  Servlet Engine
create ServletContext object as soon as the web application is deployed. This
object is only one per web application. All Servlets share this object.
ServletContext object is not directly available for servlets. To get its
reference we have to call the following method.  <o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                        ServletContext sc = getServletContext();<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Even though the above method is called on
the servlet instance, internally it is called on the ServletConfig object.
I.e., getServletContext method belongs to ServletConfig object.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">ServletContext object can be treated as
shared informatory repository for application level data. One servlet can store
data into this object and another servlet of the same application can
access  that data. A Servlet uses this
object for the following purposes.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">To Communicate with the web container<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">2.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">To talk to other servlets<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">3.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">To Share data (in the form of attributes) with
other servlets<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-left: 63.0pt; mso-add-space: auto; mso-list: l4 level1 lfo3; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">4.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">To get application level initialization
parameters known as context parameters.<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-left: 63.0pt; mso-add-space: auto; mso-list: l4 level1 lfo3; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Whenever a servlet wants to know the web container details
in which it is deployed, it can call getServletInfo method on the “sc”(ServletContext
object. To write any information into container log files we call log method on
“sc”. One servlet can store a data item into the ServletContext object by
calling setAttribute method. Another servlet can get it by calling getAttribute
method on the “sc” object.Whenever a servlet wants to communicate with the
other servlet, call getRequestDispatcher method on the “sc” object.It produces
RequestDispatcher object. Using RequestDispatcher object one servlet can
communicate with other servlets of the web application. Initialization
parameters are individual for each servlet. They are supplied from web.xml.
Aservlet retrieves them by ccalling getInitParameter() on the ServletConfig
object. When we want to supply common init parameters for all the servlets we
use context parameters.<o:p></o:p></span></div>
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<br /></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><context-param><o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <param-name>any
name</param-name><o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <param-value>anyvalue</param-value><o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"></context-param><o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<b><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">RequestDispatcher
object: <o:p></o:p></span></b></div>
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<b><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></b></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"> RequestDispatcher
object is used in the servlets to implement request dispatching. A Servlet
recives the client request, does the processing partially and hands over the
request processing duty to another servlet. This mechanism is known as request
dispatching. Inter servlet communication is implemented using RequestDispacher
object. In a servlet we can get RequestDispatcher object reference in two ways.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">RequestDispatcher rd =
context.getRequestDispatcher(String absolutepath);<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">2.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">RequestDispatcher
rd=request.getRequestDispatcher(String relativepath);<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l0 level1 lfo4; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">If we are using the ServletContext object to get the
RequestDispatcher, we have to give absolute URL of the target resource. If we
are using HttpServletRequest to get the RequestDispatcher object, we give only
relative url of the target resource.Request dispatching can be implemented in
two ways.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoListParagraphCxSpFirst" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo5; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">1.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">      
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Forward mechanism<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo5; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Georgia; mso-fareast-font-family: Georgia;">2.<span style="font-family: 'Times New Roman'; font-size: 7pt; line-height: normal;">     
</span></span><span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Include mechanism<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-left: .75in; mso-add-space: auto; mso-list: l3 level1 lfo5; text-indent: -.25in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal" style="margin-left: .5in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">You can see these functionality
and all the following video in better way.<o:p></o:p></span></div>
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<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<iframe allowfullscreen="allowfullscreen" frameborder="0" height="266" mozallowfullscreen="mozallowfullscreen" src="https://www.youtube.com/embed/qxlcsIBxKjw?feature=player_embedded" webkitallowfullscreen="webkitallowfullscreen" width="320"></iframe></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal" style="margin-left: .5in;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">See my Next post how to handle
Servlet Exception…..<o:p></o:p></span></div>
</div>

Inter Servlet Communication?

Image Source Google Images Happy Christmas Hi All my blog viewers Happy C...

What is Deployment Descriptor?

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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                         </span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                           Hello everyone my
last post one small HelloWorld Example I am showed in the video. This just for awareness
of the servlet based application. In the last I didn’t mention deployment descriptor
information in that now I am trying to give here deployment descriptor types
and what is the use of deployment descriptor.<o:p></o:p></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                        Deployment Descriptor
is a component in Java EE application that describes how a web application
should be deployed. It is an xml file provided with each module of the
application. It describes the configuration information for that module. It must
e placed in WEB-INF directory, directly under the web application root. There are
different kinds of deployment descriptor. Hey common I am giving these
information into video while reading some people may not interest just simply relax
and see video is enough that the reason I am giving here video why your late
let see the video <o:p></o:p></span></div>
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<br />
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<iframe allowfullscreen="allowfullscreen" frameborder="0" height="266" mozallowfullscreen="mozallowfullscreen" src="https://www.youtube.com/embed/5RXakZ4zgnU?feature=player_embedded" webkitallowfullscreen="webkitallowfullscreen" width="320"></iframe></div>
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<br /></div>
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<br /></div>
</div>
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<br /></div>
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<br /></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Like that we can add the
following information in deployment descriptor.<o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><servlet><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <servlet-name>ShowRequestHeaders</servlet-name><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <servlet-class> ShowRequestHeaders</servlet-class><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"></servlet><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"><servlet-mapping><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <servlet-name> ShowRequestHeaders</servlet-name><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">            <url-pattern>/req</url-pattern><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"></servlet-mapping><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;"></web-app><o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Add more number of deployment
descriptor elements while using EJB in the application.<o:p></o:p></span></div>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<div class="MsoNormal" style="text-align: justify;">
<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">Next post on Request and
Response Headers…………….<o:p></o:p></span></div>
</div>

What is Deployment Descriptor?

Hello everyone my last post one small HelloWorld Example I am showed in the video....

HelloWorld Servlet Example

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<span style="font-family: "Georgia","serif"; font-size: 12.0pt; line-height: 115%;">                     </span><span style="font-size: 12pt; line-height: 115%;"><span style="font-family: Georgia, Times New Roman, serif;"> Hello Every one in this post 
I am trying to develop one simple HelloWorld servlet application. Here
also I am showing these steps through video. Please watch each step by step and
implement in your system I know you never forgot any single piece of step. Here
I am telling one there is lot of open source and books and many more available
I am not blamed any one there is different kind of approaches. I feel this is
one kind of approaches you may like or dislike. But one think I tell once I can
read any story it may lost after few days if you implement those reading
concepts or visualizing you never forgot right friends.<o:p></o:p></span></span></div>
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<span style="font-size: 12pt; line-height: 115%;"><span style="font-family: Georgia, Times New Roman, serif;"><br /></span></span></div>
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<span style="font-size: 12pt; line-height: 115%;"><span style="font-family: Georgia, Times New Roman, serif;">                        In
my previous post how many type of servlets available. What are the methods we
need to implement, what is the syntax kind of information you understand. Now
the time is understanding points implementation time right see the following
video and implement step by step. Hello friends one thing I can tell you better
to practice once after see this, if you feel its not understanding better to
see twice and implement after your confidence level defiantly increased.</span><span style="font-family: Georgia, serif;"><o:p></o:p></span></span></div>
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<iframe allowfullscreen="allowfullscreen" frameborder="0" height="266" mozallowfullscreen="mozallowfullscreen" src="https://www.youtube.com/embed/oEZ9mRdDMaI?feature=player_embedded" webkitallowfullscreen="webkitallowfullscreen" width="320"></iframe></div>
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<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<br /></div>
<a class="g-profile" href="http://plus.google.com/113781836164165339620" target="_blank">+Chandra Sekhar</a>          Next post we will much more details about servlets...............<br />
<br /></div>
</div>

HelloWorld Servlet Example

Hello Every one in this post I am trying to develop one simple HelloWorld servlet application. Here also I am sho...