Duplicated Session Variables
We don't have any need to create a new session variable
because it has been created by the JSP container for you. Now consider a case
where you want to use the another variable by the same name, for e.g. we want to
use "session" for two times with the same name. Consider we have
declared a session variable true in jsp page <%@ page session =
"true"> and we want to use it again by using <% HttpSession
session = request.getSession();%>. You will get an error saying
"Duplication of local variable" because we can't declare a same
variable twice.
Now consider a case we want to use the same variable
name. At this situation we can solve this problem by using the <jsp: useBean>
standard action tag.
The code of the program is given below:
package Mybean;
public class DuplicatedSessionJavaBean{
private String name;
private String pwd;
private String email;
public void setName(String name){
this.name = name;
}
public String getName(){
return name;
}
public void setPwd(String pwd){
this.pwd = pwd;
}
public String getPwd(){
return pwd;
}
public void setEmail(String email){
this.email = email;
}
public String getEmail(){
return email;
}
}
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<jsp:useBean id="duplicatedSession" class=
"Mybean.DuplicatedSessionJavaBean" scope="session">
<%-- The setProperty tag is only executed when a
JavaBean is created --%>
<jsp:setProperty name=
"duplicatedSession" property="name" value="James" />
<jsp:setProperty name=
"duplicatedSession" property="pwd" value="xyx" />
<jsp:setProperty name=
"duplicatedSession" property="email" value="
jamesbond@rediffmail.com" />
</jsp:useBean>
<html>
<head>
<title>When a JavaBean already exists...</title>
</head>
<body>
The username is :<jsp:getProperty name="
duplicatedSession" property="name" /><P>
The password is :<jsp:getProperty name="
duplicatedSession" property="pwd" /><P>
The email is :<jsp:getProperty name
="duplicatedSession" property="email" /><P>
<a href="DuplicatedBean.jsp"><h1>Click
</h1></a><br> to
see another page that has the use <br>
the same JavaBean with same name and scope.
</body>
</html>
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<jsp:useBean id="duplicatedSession" class="
Mybean.DuplicatedSessionJavaBean"
scope="session" />
<html>
<head>
<title>When a JavaBean already exists...</title>
</head>
<body>
<h1>Java Bean is already exist by this name and scope</h1>
<P>
The userName is :<jsp:getProperty
name="duplicatedSession" property="name" /><P>
The password is :<jsp:getPropert
y name="duplicatedSession" property="pwd" /><P>
The email is :<jsp:getPropert
y name="duplicatedSession" property="name" /><P>
</body>
</html>
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The output of the program is given below:
Download
this example.
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Y! MyWeb
