NullpointerException Binding does not work JSF bean

Question

I created a simple HtmlInputText

  <h:inputText binding="#{IndexBean.objUIInput}" />

Then in my managed bean this is: -

   private   UIInput objUIInput;

    public UIInput getObjUIInput() {
        objUIInput.setValue("laala");
        return objUIInput;
    }

    public void setObjUIInput(UIInput objUIInput) {
        System.out.println("Set!!");
        this.objUIInput = objUIInput;
    }

But I always get a NullpointerException. Do I need to do anything on my JSF page? how do we do jsp: usebean setproperty? Please help me.

Answer 1

If you want to change the default state / behavior of the component before displaying, you need to create an instance . That is, at the time of the announcement:

private UIInput objUIInput = new HtmlInputText();

or during construction:

public Bean() {
    this.objUIInput = new HtmlInputText();
}

or, as God suggested, using @PostConstruct:

@PostConstruct
public void init() {
    this.objUIInput = new HtmlInputText();
}

(which will be executed after building the bean and initializing / configuring all managed properties).

, - - getters/seters. bean, bean .

UIInput#setValue() setter. JSF .

public void setObjUIInput(UIInput objUIInput) {
    this.objUIInput = objUIInput;
    this.objUIInput.setValue("laala");
}

Answer 2

, - get/set - .

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