class

The fully qualified name of the class that defines the implementation of 

the object. The class name is case sensitive.

If the class and beanName attributes are not specified the object must 

be present in the given scope.

beanName

The name of a Bean, as expected by the instantiate() method of the 

java.beans.Beans

 class.

This attribute can accept a request time attribute expression as a value.

type

If specified, it defines the type of the scripting variable defined.

This allows the type of the scripting variable to be distinct from, but 

related to, that of the implementation class specified.

The type is required to be either the class itself, a superclass of the 

class, or an interface implemented by the class specified. 

The object referenced is required to be of this type, otherwise a 

java.lang.ClassCastException

 shall occur at request time 

when the assignment of the object referenced to the scripting variable 

is attempted.

If unspecified, the value is the same as the value of the 

class

attribute.

2.13.2

The 

jsp:setProperty

 action sets the value of properties in a Bean. The 

name

 attribute 

denotes an object that must be defined before this action appears.

There are two variants of the jsp:setProperty action. Both variants set the values of one or 

more properties in the Bean based on the type of the properties. The usual Bean introspection 

is done to discover what properties are present, and, for each, its name, whether they are 

simple or indexed, their type, and setter and getter methods.

Properties in a Bean can be set from one or more parameters in the request object, from a 

String constant, or from a computed request time expression. Simple and indexed properties 

can be set using setProperty. The only types of properties that can be assigned to from String 

constants and request parameter values are those listed in 

TABLE 2 4

; the conversion applied 

is that shown in the table. Request time expressions can be assigned to properties of any 

type; no automatic conversions will be performed.

When assigning values to indexed properties the value must be an array; the rules described 

in the previous paragraph apply to the elements.

Chapter 2

Standard Syntax and Semantics

64