Explain the life cycle of servlet?
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Answer / surajkumar.java
1. The servlet is controlled by the container in which the
servlet has been deployed. When a request is made to a
servlet, its mapping is searched in web.xml. If mapping
found then the web container loads the servlet class and
creates an instance of it and initializes (e.g servlet
context parameters, database connections objects etc) the
servlet instance by calling the init method.
2. Then invokes the service method, passing a request and
response object. The service provided by a servlet is
implemented in the service method of a GenericServlet and
the doMethod methods (where Method can take the value like
Get, Delete, Options, Post, Put, Trace) of an
HttpServlet. Basically a service method extract information
from the request, access external resources, and then
populate the response based on that information.
3. The container calls destroy method to remove servlet
instance. We also do some specialized handling like closing
a connection, freeing the memory used by local variables etc
by explicitly defining the destroy method inside a servlet
class.
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Answer / sasi kumar
Initialization:A servlet is first loaded and initialized
usually when it is request by the corresponding client.
Service:After initilization,the servlet serve client on
request,implementing the application logic clients of the
web application they belong to.
Destruction:When all pending request are processed and the
servlets have been idle for a specific amount of time,they
may be destroy by the servlet and release all the resources
they occupy.
| Is This Answer Correct ? | 0 Yes | 0 No |
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