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44

Chapter 2 First Servlets

Figure 2 7

Specifying initialization parameters for a named servlet with the Java Web 

Server.

2.8 An Example Using Servlet Initialization 

and Page Modification Dates

Listing 2.11 shows a servlet that uses 

init

 to do two things. First, it builds an

array of 10 integers. Since these numbers are based upon complex calcula 

tions, I don't want to repeat the computation for each request. So I have

doGet

 look up the values that 

init

 computed instead of generating them

each time. The results of this technique are shown in Figure 2 8. 

However, since all users get the same result, 

init

 also stores a page modifi 

cation date that is used by the 

getLastModified

 method. This method should

return a modification time expressed in milliseconds since 1970, as is standard

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