getProtocol() method is defined in ServletRequest interface from javax.servlet package and inherited by HttpServletRequest. With getProtocol() method, the Servlet Programmer can know what protocol (like HTTP/1.0 or HTTP/1.1) is used by the client from HTML file to call the Servlet. Let us see what Java API says about this method. java.lang.String getProtocol(): Returns the name …
getMethod() method is defined in HttpServletRequest interface from javax.servlet.http package. With getMethod() method, the Servlet Programmer can know what method (either get or post) is used by the client from HTML file to call the Servlet. Let us see what Java API says about this method. java.lang.String getMethod(): Returns the name of the HTTP method …
Programmer uses getServletPath() method to retrieve the alias name used by client. getServletPath() Method is defined in ServletRequest inherited by HttpServletRequest. This program uses getServletPath() of HttpServletRequest to retrieve the alias name (of <servlet-mapping>) tag. Client uses this alias name to call the Servlet. Following is the method signature. Method is defined in HttpServletRequest interface. …
getRequestURL() vs getRequestURI() methods are used by Servlet Programmer to retrieve the URL particulars of client. getRequestURL() and getRequestURI() methods are defined in HttpServletRequest interface. These two are used by the Servlet to retrieve the URL information (written in ACTION attribute of FORM tag) used by the client to call the servlet. getRequestURL() vs getRequestURI() …
What is client data? When the user clicks the submit button, we think that the data entered by the user like user name and password are sent to the server. Ofcourse, right. But along with it, lot of client data goes to the server. The client data includes the protocol used by the client to …
What is client data? getRequestURL(): When the user clicks the submit button, we think that the data entered by the user like user name and password are sent to the server. Ofcourse, right. But along with it, lot of client data goes to the server. The client data includes the protocol used by the client, …
It is the modification of the first program Login Validation. The modification is instead of sending INVALID message, a new HTML form is sent to the user wherein the user can fill up again and send. This HTML form is existing already on the server. It is not created on the fly. That is why, …
sendRedirect() Example Servlets – Send HTML form to Client Read More »
In this example, a dynamically created HTML form is sent to the client on-the-fly. Start reading. his is the modified code of the Login Screen Validation. In the first program, the user name and password are read by the Servlet, validated and sent back the result of validation (valid or invalid) as response. The modification …
Send Dynamically created HTML form to client in Servlets Read More »
A Servlet may have some values needed for it’s execution or a Programmer may require some values to be fed to Servlet needed in the coding for execution. These values are specific to a particular Servlet and not required for all Servlets. For this, the deployment descriptor web.xml, comes with <init-param> tag and an example …
ServletConfig Example init-param read getInitParameter() Read More »
In the first simple program Login Screen Validation, the data sent by the client is extracted from HttpServletRequest object req, using getParameter(String) method. The getParameter(String) method works to read a single text box (or any FORM field) only. The HttpServletRequest interface comes with another method getParameterNames() (inherited from ServletRequest interface) to read all the FORM …
Read Client HTML Form data with getParameterNames() Read More »
1. What is Deployment? Copying the .class file of the Servlet from the current directory to the classes folder of Tomcat (or any Web server) is known as deployment. When deployed, Tomcat is ready to load and execute the Servlet, at anytime, at the client request. 2. What is Deployment Descriptor? As the name indicates, …
Servlets Tomcat: Install Tomcat server of your choice version by downloading from Apache site. Many versions of Tomcat can be found in the following link. http://tomcat.apache.org/download-60.cgi Check with the documentation of what JDK or JRE version is compatible to the specific Tomcat version. For example I loaded Tomcat 5.0 and is compatible with JDK 6.0. …
After going through the introduction and architecture of servlets, let us write a simple Login Validation program. As you have seen in the architecture, there will be two programs – one running on client machine and the other on server. Servlet Example explained in 10 steps First let us write the client-side program. I. Client …
For easy understanding, the Servlets Tutorial Architecture is given in Question/Answer format. 1. What is Component? A Component is a reusable software unit. 2. What is server-side component? In client/server communication, a server-side component is that one which is automatically invoked against client request, executed and responses to client fulfilling the requirement. 3. What is …
