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How to enforce jsf to create new instance of bean instead of throwing NullPointerException?

I'm almost sure that I do something wrong and thus the question's title is a bit incorrect.

I have a form with several fields for creating a new User-objects (fields like login, password, birthday etc). And I have 2 buttons - Cancel and Create. I didn't finish Create yet :) , but when I press Cancel I see NullPointerException. Here is simplified code:

<f:view>
    <h:form>
        <h:panelGroup layout="block">       
            <h:inputText id="add_login" value="#{userSupport.user.login}"/>
            <h:inputSecret id="add_password" value="#{userSupport.user.password}"/>
            <h:inputText id="add_name" value="#{userSupport.开发者_如何学编程user.name}"/>
            <h:inputText id="add_surname" value="#{userSupport.user.surname}"/>

            <h:commandButton value="Cancel" action="cancel"/>
        </h:panelGroup>
    </h:form>
</f:view>

UserSupport class has field user with getter and setter and some other methods. It's a Spring bean with Session scope.

When I press cancel, I see NPE because jsf tries to save values from inputs in user-object, but user-object is null.

What is the correct way of doing this?


on your cancel button set immediate="true" This will skip all the "unwanted" phases.

The same problem, however, will arise with your "create" button, and you shouldn't use immediate there. Better initialize the user property - either in constructor, or using the @PostConstruct annotation on a method, which does the initialization actions.

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