Using JavaBeans with Struts Tags
In many
cases, you’ll use the tags from the various tag
libraries in conjunction with JavaBeans. The JavaBeans may be
ActionForm
s, whose properties correspond to input
fields in the HTML form. In other cases, however, the beans will be
ordinary value objects from the model layer. These beans can be in
any scope: page, request, session, or application.
There are three ways to access the properties of a JavaBean:
Accessing simple properties
Accessing nested properties
Accessing indexed properties
Accessing Simple Properties
Accessing simple bean properties works similarly
to the JSP <jsp:getProperty>
action. A
reference to a property named
“firstName” is converted into a
method call to getFirstName( )
or
setFirstName(value)
, using the standard JavaBeans
specification naming conventions for bean properties.
Struts uses the Java introspection APIs to identify the names of the
actual property getter and setter methods, so your beans can provide
customized method names through the use of a
BeanInfo
class. See the
JavaBeans
specification, available at http://java.sun.com/products/javabeans/, for
more information.
Accessing Nested Properties
Nested references are used to access a property through a hierarchy of property names separated by periods ( . ), similar to the way that nested properties are accessed in JavaScript. For example, the following property reference:
property="user.address.city"
is translated into the equivalent Java expression:
getUser().getAddress().getCity( ...
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