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Servlet - Session



//returns null if no session already exists for the current client

HttpSession session = request.getSession(false);

// creates a new session if no session already exists
// HttpSession session = request.getSession();

if (session == null) {
printMessageSayingCartIsEmpty();
} else {
extractCartAndPrintContents(session);
}


SomeClass value =
(SomeClass)session.getAttribute("someIdentifier");


if (value == null) { // No such object already in session
value = new SomeClass(...);
session.setAttribute("someIdentifier", value);
}

removeAttribute(String name)


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