JSF多字段验证NULLPointerException

Question

<h:form id="form">
Username: <br/>
<h:inputText id="username" value="#{home.username}" required="true" >
<f:validator validatorId="loginValidator"></f:validator> 
<f:attribute name="passwordComponent" value="#{passwordComponent}" ></f:attribute>
</h:inputText>
<br/>
Password: <br />
<h:inputText id="password"  bindig="#{passwordComponent}" value="#{home.password}"  required="true"></h:inputText>
<br/>
<h:commandButton value="login" id="login" action="#{home.login}"></h:commandButton>
</h:form>



public class LoginValidator implements Validator {

@Override
public void validate(FacesContext context, UIComponent component, Object value)
        throws ValidatorException {
    String username = (String)value;
    UIInput passwordInput = (UIInput)component.getAttributes().get("passwordComponent");
    String password = (String) passwordInput.getValue();

    if(username!="aa" || password!="aa"){
        passwordInput.setValid(false);
        throw new ValidatorException(new FacesMessage("Wrong username or password!"));
    }
}

}

在这一行我得到了NuulPointerException：

String password =（String）passwordInput.getValue（）;

为什么？

Answer 1

“绑定”一词的拼写在下一行中不正确。

<h:inputText id="password"  bindig="#{passwordComponent}"...

将 bindig 更改为绑定。