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q on jsp:useBean  RSS feed

 
JayaSiji Gopal
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whic of the following useBean actions allow u to locate an instance of the bean called "myBean"with id ="thebean" in session scope, without creating a new instance, if one is not existent already?

<jsp:useBean id="thebean" type="MyBean" scope="session">
<jsp:useBean id="thebean" class="MyBean" scope="session">
<jsp:useBean id="thebean" beanName="myBean" type="MyBean" scope="session">
<jsp:useBean id="thebean" type="MyBean" create="false" scope="session">

I guess it is the first one. Am i right? Otherwise, the first line will throw a compile time error.
 
Priya Jothi
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Option 1 is correct.But i dont think it'll throw compile time error if the bean doesn't exist already..it'll throw null pointer if you attempt to use such bean in ur code.Correct me guys if am wrong.

Regards,
Priya.
 
Vishnu Prakash
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Option 1 is correct.

If the bean doesn't exist it throws a java.lang.InstantiationException
 
M Rama
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can you guys explain why 1 is correct? also, this question means that there has been a session.setAttribute("myBean", xxx) where xxx is a MyBean object. the object xxx needs to be referenced by thebean using the useBean in the JSP and not create a new instance if already not existing. is this right???

btw JayaSiji Gopal where are you getting your questions from? seems like the wordings are confusing.
 
It is sorta covered in the JavaRanch Style Guide.
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