Using Sessions

HttpSession session = request.getSession(true);

ShoppingCart cart =

(ShoppingCart)session.getAttribute("shoppingCart");

if (cart == null) { // No cart already in session

cart = new ShoppingCart();

session.setAttribute("shoppingCart", cart);

}

doSomethingWith(cart);

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HttpSession Methods

getAttribute, getValue [2.1]

Extracts a previously stored value from a session object. 

Returns null if no value is associated with given name

setAttribute, putValue [2.1] 

Associates a value with a name. Monitor changes: values 

implement HttpSessionBindingListener.

removeAttribute, removeValue [2.1] 

Removes values associated with name 

getAttributeNames, getValueNames [2.1] 

Returns names of all attributes in the session

getId 

Returns the unique identifier

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