Prentice.Hall.Introduction.to.Java.Programming,.Brief.Version.9th.(2014).[sharethefiles.com]

The getResponse method converts guessString from the user input to an
integer (line 28) and determines if the guess is too low (line 30), too
high (line 34), and just right (line 32).
Listing 44.10 GuessNumber.xhtml
Guess a number
The bean property guessString is bound to the text input (line 14). The
CSS style text-align: right (line 13) specifies that the text is rightaligned
in the input box.
The CSS style margin-left: 60px (line 15) specifies that the command
button has a left margin of 60 pixels.
The bean property response is bound to the text output (line 18). The
CSS style color: red (line 17) specifies that the text is displayed in
red in the output box.
The project uses the view scope. What happens if the scope is changed to
the request scope? Every time the page is refreshed, JSF creates a new
bean with a new random number. What happens if the scope is changed to
the session scope? The bean will be alive as long as the browser is
alive. What happens if the scope is changed to the application scope?
The bean will be created once when the application is launched from the
server.
44.7 Validating Input
In the preceding GuessNumber page, an error would occur if you entered a
non-integer in the input box before clicking the Guess button. A simple
way to fix the problem is to check the text field before processing any
event. JSF provides several convenient and powerful ways for input
validation. You can use the standard validator tags in the JSF Core Tag
Library or create custom validators. Table 44.2 lists some JSF input
validator tags.
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