How do I access servlet context?
Example of getServletContext() method
- //We can get the ServletContext object from ServletConfig object.
- ServletContext application=getServletConfig().getServletContext();
- //Another convenient way to get the ServletContext object.
- ServletContext application=getServletContext();
What is get servlet context?
Interface ServletContext. public interface ServletContext. Defines a set of methods that a servlet uses to communicate with its servlet container, for example, to get the MIME type of a file, dispatch requests, or write to a log file. There is one context per “web application” per Java Virtual Machine.
How do I connect one servlet to another?
To forward request from one servlet to other either you can user RequestDispatcher or SendRedirect. To use RequestDispatcher you must have to get ServletContext reference and then you have to call the getRequestDispatcher() method of ServletContext and using SendRedirect you have to write response. sendRedirect(“URL”).
Which method of ServletContext returns the name and version of the servlet container on which the servlet is running?
getServerInfo()
What is the difference between servlet config and servlet context?
ServletConfig is an object containing some initial parameters or configuration information created by Servlet Container and passed to the servlet during initialization. ServletConfig is for a particular servlet, that means one should store servlet specific information in web.
Is servlet a class?
A servlet is a Java programming language class that is used to extend the capabilities of servers that host applications accessed by means of a request-response programming model. Although servlets can respond to any type of request, they are commonly used to extend the applications hosted by web servers.
What is servlet Mapping?
Servlet mapping specifies the web container of which java servlet should be invoked for a url given by client. It maps url patterns to servlets. When there is a request from a client, servlet container decides to which application it should forward to. servlet-mapping has two child tags, url-pattern and servlet-name.
Why init () is used in servlet?
init. Called by the servlet container to indicate to a servlet that the servlet is being placed into service. The servlet container calls the init method exactly once after instantiating the servlet. The init method must complete successfully before the servlet can receive any requests.
What is servlet-name?
The servlet-name element declares a name for this particular servlet instance. Each servlet instance in a context must have a unique name. However, the name is only used to associate URL mappings with this instance, and need not correspond to the name of the servlet class or the URL of the servlet.
What is servlet XML?
Applicationcontext. xml – It is standard spring context file which contains all beans and the configuration that are common among all the servlets. It is optional file in case of web app. Spring uses ContextLoaderListener to load this file in case of web application.
What is use of Web xml file in java?
Web. xml file is the configuration file of web applications in java. It instructs the servlet container which classes to load, what parameters to set in the context, and how to intercept requests coming from browsers. Web. xml is called as deployment descriptor file.
How do I map a servlet in Web xml?
To map a URL to a servlet, you declare the servlet with the element, then define a mapping from a URL path to a servlet declaration with the element.
What is the difference between CGI and servlet?
All the programs of Servlets are written in JAVA and they get to run on JAVA Virtual Machine….Difference between Java Servlet and CGI.
| Basis | Servlet | CGI |
|---|---|---|
| Data Sharing | Data sharing is possible. | Data sharing is not possible. |
| Link | It links directly to the server. | It does not links directly to the server. |
What is CGI servlet?
CGI stands for Common Gateway Interface; it is an API for writing applications (often scripts) that can be run by a web server to service a particular range of URLs. Servlets are an implementation very similar to CGI using a component-ized framework in Java.
What do you mean by CGI?
Common Gateway Interface
What is the main drawback of CGI?
One major drawback with CGI is that it launches a new program each time a user clicks on a form, so Web servers used for heavily trafficked sites could be running thousands of programs at once — a huge drain on Web-site performance.
What is the disadvantages of CGI?
Disadvantages of CGI: In Common Gateway Interface each page load incurs overhead by having to load the programs into memory. Generally, data cannot be easily cached in memory between page loads. There is a huge existing code base, much of it in Perl. CGI uses up a lot of processing time.