Package javax.faces.component

Class UISelectMany

  • All Implemented Interfaces:
    java.util.EventListener, EditableValueHolder, PartialStateHolder, StateHolder, TransientStateHolder, ValueHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder
    Direct Known Subclasses:
    HtmlSelectManyCheckbox, HtmlSelectManyListbox, HtmlSelectManyMenu
    public class UISelectMany
extends UIInput

    UISelectMany is a UIComponent that represents the user's choice of a zero or more items from among a discrete set of available options. The user can modify the selected values. Optionally, the component can be preconfigured with zero or more currently selected items, by storing them as an array or Collection in the value property of the component.

    This component is generally rendered as a select box or a group of checkboxes.

    By default, the rendererType property must be set to "javax.faces.Listbox". This value can be changed by calling the setRendererType() method.

    The Renderer for this component must perform the following logic on getConvertedValue():

      Obtain the Converter using the following algorithm:

        If the component has an attached Converter, use it.

        If not, look for a ValueExpression for value (if any). The ValueExpression must point to something that is:

        • An array of primitives (such as int[]). Look up the registered by-class Converter for this primitive type.

        • An array of objects (such as Integer[] or String[]). Look up the registered by-class Converter for the underlying element type.

        • A java.util.Collection. Do not convert the values.

        If for any reason a Converter cannot be found, assume the type to be a String array.

      Use the selected Converter (if any) to convert each element in the values array from the request to the proper type, and store the result of each conversion in a data structure, called targetForConvertedValues for discussion. Create targetForConvertedValues using the following algorithm.

      • If the component has a ValueExpression for value and the type of the expression is an array, let targetForConvertedValues be a new array of the expected type.

      • If the component has a ValueExpression for value, let modelType be the type of the value expression. If modelType is a Collection, do the following to arrive at targetForConvertedValues:

        • Ask the component for its attribute under the key "collectionType", without the quotes. If there is a value for that key, the value must be a String that is a fully qualified Java class name, or a Class object, or a ValueExpression that evaluates to a String or a Class. In all cases, the value serves to identify the concrete type of the class that implements Collection. For discussion, this is called collectionType. Let targetForConvertedValues be a new instance of Collection implemented by the concrete class specified in collectionType. If, collectionType can not be discovered, or an instance of Collection implemented by the concrete class specified in collectionType cannot be created, throw a FacesException with a correctly localized error message. Note that FacesException is thrown instead of ConverterException because this case would only arise from developer error, rather than end-user error.

        • If there is no "collectionType" attribute, call getValue() on the component. The result will implement Collection. If the result also implements Cloneable, let targetForConvertedValues be the result of calling its clone() method, then calling clear() on the cloned Collection. If unable to clone the value for any reason, log a message and proceed to the next step.

        • If modelType is a concrete class, let targetForConvertedValues be a new instance of that class. Otherwise, the concrete type for targetForConvertedValues is taken from the following table. All classes are in the java.util package. All collections must be created with an initial capacity equal to the length of the values array from the request.

          If modelType is an instance of then targetForConvertedValues must be an instance of
          SortedSet TreeSet
          Queue LinkedList
          Set HashSet
          anything else ArrayList

      • If the component does not have a ValueExpression for value, let targetForConvertedValues be an array of type Object.

      Return targetForConvertedValues after populating it with the converted values.

    • Field Detail

      • COMPONENT_TYPE

        public static final java.lang.String COMPONENT_TYPE

        The standard component type for this component.

        See Also:
        Constant Field Values

      • COMPONENT_FAMILY

        public static final java.lang.String COMPONENT_FAMILY

        The standard component family for this component.

        See Also:
        Constant Field Values

      • INVALID_MESSAGE_ID

        public static final java.lang.String INVALID_MESSAGE_ID

        The message identifier of the FacesMessage to be created if a value not matching the available options is specified.

        See Also:
        Constant Field Values

    • Constructor Detail

      • UISelectMany

        public UISelectMany()

        Create a new UISelectMany instance with default property values.

    • Method Detail

      • getFamily

        public java.lang.String getFamily()
        Description copied from class: UIComponent

        Return the identifier of the component family to which this component belongs. This identifier, in conjunction with the value of the rendererType property, may be used to select the appropriate Renderer for this component instance.

        Overrides:
        getFamily in class UIInput

      • getSelectedValues

        public java.lang.Object[] getSelectedValues()

        Return the currently selected values, or null if there are no currently selected values. This is a typesafe alias for getValue().

      • setSelectedValues

        public void setSelectedValues​(java.lang.Object[] selectedValues)

        Set the currently selected values, or null to indicate that there are no currently selected values. This is a typesafe alias for setValue().

        Parameters:
        selectedValues - The new selected values (if any)

      • getValueBinding

        public ValueBinding getValueBinding​(java.lang.String name)
        Deprecated.
        this has been replaced by getValueExpression(java.lang.String).

        Return any ValueBinding set for value if a ValueBinding for selectedValues is requested; otherwise, perform the default superclass processing for this method.

        This method relies on the superclass to provide the ValueExpression to ValueBinding wrapping.

        Overrides:
        getValueBinding in class UIComponentBase
        Parameters:
        name - Name of the attribute or property for which to retrieve a ValueBinding
        Throws:
        java.lang.NullPointerException - if name is null

      • getValueExpression

        public javax.el.ValueExpression getValueExpression​(java.lang.String name)

        Return any ValueExpression set for value if a ValueExpression for selectedValues is requested; otherwise, perform the default superclass processing for this method.

        Overrides:
        getValueExpression in class UIComponent
        Parameters:
        name - Name of the attribute or property for which to retrieve a ValueExpression
        Throws:
        java.lang.NullPointerException - if name is null
        Since:
        1.2

      • setValueExpression

        public void setValueExpression​(java.lang.String name,
                               javax.el.ValueExpression binding)

        Store any ValueExpression specified for selectedValues under value instead; otherwise, perform the default superclass processing for this method.

        Overrides:
        setValueExpression in class UIComponent
        Parameters:
        name - Name of the attribute or property for which to set a ValueExpression
        binding - The ValueExpression to set, or null to remove any currently set ValueExpression
        Throws:
        java.lang.NullPointerException - if name is null
        Since:
        1.2

      • compareValues

        protected boolean compareValues​(java.lang.Object previous,
                                java.lang.Object value)

        Return true if the new value is different from the previous value. Value comparison must not be sensitive to element order.

        Overrides:
        compareValues in class UIInput
        Parameters:
        previous - old value of this component
        value - new value of this component

      • validateValue

        protected void validateValue​(FacesContext context,
                             java.lang.Object value)

        In addition to the standard validation behavior inherited from UIInput, ensure that any specified values are equal to one of the available options. Before comparing each option, coerce the option value type to the type of this component's value following the Expression Language coercion rules. If the specified value is not equal to any of the options, enqueue an error message and set the valid property to false.

        This method must explicitly support a value argument that is a single value or a value argument that is a Collection or Array of values.

        If UIInput.isRequired() returns true, and the current value is equal to the value of an inner UISelectItem whose UISelectItem.isNoSelectionOption() method returns true, enqueue an error message and set the valid property to false.

        Overrides:
        validateValue in class UIInput
        Parameters:
        context - The FacesContext for the current request
        value - The converted value to test for membership.
        Throws:
        java.lang.NullPointerException - if context is null