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The jsp:useBean Action
This action lets you load in a JavaBean to be used in the JSP page. This is a a very useful capability because it lets you exploit the reusability of Java classes without sacrificing the convenience that JSP adds over servlets alone. The simplest syntax for specifying that a bean should be used is:
<jsp:useBean id="name" class="" />
This usually means "instantiate an object of the class specified by class, and bind it to a variable with the name specified by id." However, as we'll see shortly, you can specify a scope attribute that makes the bean associated with more than just the current page. In that case, it is useful to obtain references to existing beans, and the jsp:useBean action specifies that a new object is instantiated only if there is no existing one with the same id and scope. Now, once you have a bean, you can modify its properties via jsp:setProperty, or by using a scriptlet and calling a method explicitly on the object with the variable name specified earlier via the id attribute. Recall that with beans, when you say "this bean has a property of typeX called foo", you really mean "this class has a method called getFoo that returns something of type X, and another method called setFoo that takes an X as an argument." The jsp:setProperty action is discu