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190

Chapter 8 Handling Cookies

Figure 8 3

Result of visiting the ShowCookies servlet within an hour of visiting 

SetCookies in a different browser session.

8.5 Basic Cookie Utilities

This section presents some simple but useful utilities for dealing with cookies. 

Finding Cookies with Specified Names

Listing 8.3 shows a section of 

ServletUtilities.java

 that simplifies the

retrieval of a cookie or cookie value, given a cookie name. The 

getCookie 

Value

 method loops through the array of available 

Cookie

 objects, returning

the value of any 

Cookie

 whose name matches the input. If there is no match,

the designated default value is returned. So, for example, my typical

approach for dealing with cookies is as follows:

Cookie[] cookies = request.getCookies();

String color = 

ServletUtilities.getCookieValue(cookies, "color", "black");

String font =

ServletUtilities.getCookieValue(cookies, "font", "Arial");

The 

getCookie

 method also loops through the array comparing names,

but returns the actual 

Cookie

 object instead of just the value. That method is

for cases when you want to do something with the 

Cookie

 other than just

read its value.

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