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The moose likes Web Component Certification (SCWCD/OCPJWCD) and the fly likes doHead method Big Moose Saloon
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doHead method

Rohit W. Tawde

Joined: Mar 12, 2013
Posts: 25

How can i implement the doHead method ???
Which headers do i have to set explicitly in the doHead method ?
Which headers are set implicitly by the Servlet Container ?
What about the Last-Modified and If-Modified-Since headers ?

Say For Example :-
If a resource requested by a client is big (say 50 MB) , then we have to write the doHead() method, in which i would get last modified time and compare it with the If-Modified-Since header of the request and then send the response to the client ???
And if there is a change in the resource, then the client would send a GET request.

How does the browser send a HEAD and GET request. Is it related to browser programming ???
Or how could i send a HEAD request to the server if i wanted to ???

How to implement the getLastModified() method ???
Also how to implement the doHead() method ???

Could anybody please help me with the java code for these methods ???

Rohit Tawde (SCJP5)
Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42965
HEAD is not about headers at all. HEAD should do exactly the same as GET, except that it returns an empty HTTP body.
Rohit W. Tawde

Joined: Mar 12, 2013
Posts: 25

Could anybody provide me the code which has proper implementation of the doHead() method for the example stated above.
Bear Bibeault
Author and ninkuma

Joined: Jan 10, 2002
Posts: 63865

Please read NotACodeMill.

Do you even know what you want to do in these methods? If not, why do you think that they even need to be implemented? If you do, lists the steps that your code needs to take and we can address them one by one.

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I agree. Here's the link:
subject: doHead method
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