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Chapter 13 Using JavaBeans with JSP

JSWDK 1.0.1:

install_dir/webpages/WEB INF/servlets/lima/Fordhook.cl

ass

Java Web Server 2.o:

install_dir/classes/lima/Fordhook.class

The JSP files that use bean classes don't need to be installed anywhere spe 

cial, however. As is usual with JSP files on a JSP capable server, they can be

placed anywhere that normal Web pages can be.

13.2 Example: StringBean

Listing 13.1 presents a simple class called 

StringBean

 that is in the 

core 

servlets

 package. Because the class has no public instance variables (fields)

and has a zero argument constructor since it doesn't declare any explicit con 

structors, it satisfies the basic criteria for being a bean. Since 

StringBean

 has

a method called 

getMessage

 that returns a 

String

 and another method

called 

setMessage

 that takes a 

String

 as an argument, in beans terminology

the class is said to have a 

String

 parameter called 

message

. 

Listing 13.2 shows a JSP file that uses the 

StringBean

 class. First, an

instance of 

StringBean

 is created with the 

jsp:useBean

 action as follows:

After this, the 

message

 property can be inserted into the page in either of

the following two ways:

<%= stringBean.getMessage() %>

The 

message

 property can be modified in either of the following two ways: