Class InputHidden

  • All Implemented Interfaces:
    EditableValueHolder, PartialStateHolder, StateHolder, TransientStateHolder, ValueHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, EventListener

    public class InputHidden
    extends HtmlInputHidden

    The <o:inputHidden> is a component that extends the standard <h:inputHidden> and changes the behavior to immediately convert, validate and update during apply request values phase, regardless of any conversion/validation errors on other UIInput components within the same form. The standard <h:inputHidden> follows the same lifecycle as other UIInput components which is in the end unintuive as hidden input fields are usually under control of the developer.

    Use case 1: Imagine a form with a <h:inputHidden> and a <h:inputText>. The hidden input holds some prepopulated value of a request scoped bean which is intended to be passed through to the request scoped bean instance of the next request. However, when conversion/validation fails on the text input, then the hidden input won't update the bean property and then becomes empty. I.e. the original value gets permanently lost. This can be bypassed by using ajax to update only specific fields, but this will fail when the update of the hidden input is actually needed (e.g. because the value can possibly be adjusted in action/listener method).

    Use case 2: Imagine a form with an UIInput or UICommand component whose rendered attribute relies on a request scoped bean property which is retained for the next request through a <h:inputHidden>. However, when Faces needs to decode the UIInput or UICommand component during the postback, the rendered attribute has defaulted back to false because the <h:inputHidden> hasn't yet updated the request scoped bean property yet.

    This behavior cannot be achieved by using immediate="true" on <h:inputHidden>. It would only move the conversion/validation into the apply request values phase. The model still won't be updated on time.

    Also, the <h:inputHidden> didn't support the readonly attribute. This is however useful when used in combination with a validator which should block the form submit. Since version 4.1, the <o:inputHidden> supports this use case by simply grabbing and validating the model value during the apply request values phase. The setter method associated with the model won't be invoked.


    You can use it the same way as <h:inputHidden>, you only need to change h: into o: to get the "immediate v2.0" behavior.

         <o:inputHidden value="#{bean.hidden}" />

    When using ajax, don't forget to make sure that the component is also covered by the execute attribute.

    Bauke Scholtz
    • Field Detail


        public static final String COMPONENT_TYPE
        The component type, which is "org.omnifaces.component.input.InputHidden".
        See Also:
        Constant Field Values
    • Constructor Detail

      • InputHidden

        public InputHidden()
    • Method Detail

      • decode

        public void decode​(FacesContext context)
        This override performs decode, validate and update at once.
        decode in class UIInput
      • processValidators

        public void processValidators​(FacesContext context)
        This override which does effectively nothing prevents Faces from performing validation for second time.
        processValidators in class UIInput
      • processUpdates

        public void processUpdates​(FacesContext context)
        This override which does effectively nothing prevents Faces from performing update for second time.
        processUpdates in class UIInput
      • isReadonly

        public boolean isReadonly()
        Returns whether this component is readonly. Defaults to false. Note that even when this component is readonly, all associated validators will be invoked based on the model value, not on the submitted value. Also the setter won't be invoked.
        Whether this component is readonly.
      • setReadonly

        public void setReadonly​(boolean readonly)
        Set whether this component is readonly.
        readonly - Whether this component is readonly.