Package javax.faces.component

Class UIData

java.lang.Object
javax.faces.component.UIComponent
javax.faces.component.UIComponentBase
javax.faces.component.UIData
All Implemented Interfaces:
EventListener, NamingContainer, PartialStateHolder, StateHolder, TransientStateHolder, UniqueIdVendor, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder
public class UIData extends UIComponentBase implements NamingContainer, UniqueIdVendor

UIData is a UIComponent that supports data binding to a collection of data objects represented by a DataModel instance, which is the current value of this component itself (typically established via a ValueExpression). During iterative processing over the rows of data in the data model, the object for the current row is exposed as a request attribute under the key specified by the var property.

Only children of type UIColumn should be processed by renderers associated with this component.

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

  • Field Details

    • COMPONENT_TYPE

      public static final String COMPONENT_TYPE

      The standard component type for this component.

      See Also:

    • COMPONENT_FAMILY

      public static final String COMPONENT_FAMILY

      The standard component family for this component.

      See Also:

  • Constructor Details

    • UIData

      public UIData()

      Create a new UIData instance with default property values.

  • Method Details

    • getFamily

      public 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.

      Specified by:
      getFamily in class UIComponent

    • getFirst

      public int getFirst()

      Return the zero-relative row number of the first row to be displayed.

    • setFirst

      public void setFirst(int first)

      Set the zero-relative row number of the first row to be displayed.

      Parameters:
      first - New first row number
      Throws:
      IllegalArgumentException - if first is negative

    • getFooter

      public UIComponent getFooter()

      Return the footer facet of this component (if any). A convenience method for getFacet("footer").

    • setFooter

      public void setFooter(UIComponent footer)

      Set the footer facet of this component. A convenience method for getFacets().put("footer", footer).

      Parameters:
      footer - the new footer facet
      Throws:
      NullPointerException - if footer is null

    • getHeader

      public UIComponent getHeader()

      Return the header facet of this component (if any). A convenience method for getFacet("header").

    • setHeader

      public void setHeader(UIComponent header)

      Set the header facet of this component. A convenience method for getFacets().put("header", header).

      Parameters:
      header - the new header facet
      Throws:
      NullPointerException - if header is null

    • isRowAvailable

      public boolean isRowAvailable()

      Return a flag indicating whether there is rowData available at the current rowIndex. If no wrappedData is available, return false.

      Throws:
      FacesException - if an error occurs getting the row availability

    • getRowCount

      public int getRowCount()

      Return the number of rows in the underlying data model. If the number of available rows is unknown, return -1.

      Throws:
      FacesException - if an error occurs getting the row count

    • getRowData

      public Object getRowData()

      Return the data object representing the data for the currently selected row index, if any.

      Throws:
      FacesException - if an error occurs getting the row data
      IllegalArgumentException - if now row data is available at the currently specified row index

    • getRowIndex

      public int getRowIndex()

      Return the zero-relative index of the currently selected row. If we are not currently positioned on a row, return -1. This property is not enabled for value binding expressions.

      Throws:
      FacesException - if an error occurs getting the row index

    • setRowIndex

      public void setRowIndex(int rowIndex)

      Set the zero relative index of the current row, or -1 to indicate that no row is currently selected, by implementing the following algorithm. It is possible to set the row index at a value for which the underlying data collection does not contain any row data. Therefore, callers may use the isRowAvailable() method to detect whether row data will be available for use by the getRowData() method.

      To support transient state among descendents, please consult the specification for setRowStatePreserved(boolean), which details the requirements for setRowIndex() when the rowStatePreserved JavaBeans property is set to true.

      • Save current state information for all descendant components (as described below).
      • Store the new row index, and pass it on to the DataModel associated with this UIData instance.
      • If the new rowIndex value is -1:
        • If the var property is not null, remove the corresponding request scope attribute (if any).
        • Reset the state information for all descendant components (as described below).
      • If the new rowIndex value is not -1:
        • If the var property is not null, call getRowData() and expose the resulting data object as a request scope attribute whose key is the var property value.
        • Reset the state information for all descendant components (as described below).

      To save current state information for all descendant components, UIData must maintain per-row information for each descendant as follows:

      • If the descendant is an instance of EditableValueHolder, save the state of its localValue property.
      • If the descendant is an instance of EditableValueHolder, save the state of the localValueSet property.
      • If the descendant is an instance of EditableValueHolder, save the state of the valid property.
      • If the descendant is an instance of EditableValueHolder, save the state of the submittedValue property.

      To restore current state information for all descendant components, UIData must reference its previously stored information for the current rowIndex and call setters for each descendant as follows:

      • If the descendant is an instance of EditableValueHolder, restore the value property.
      • If the descendant is an instance of EditableValueHolder, restore the state of the localValueSet property.
      • If the descendant is an instance of EditableValueHolder, restore the state of the valid property.
      • If the descendant is an instance of EditableValueHolder, restore the state of the submittedValue property.
      Parameters:
      rowIndex - The new row index value, or -1 for no associated row
      Throws:
      FacesException - if an error occurs setting the row index
      IllegalArgumentException - if rowIndex is less than -1

    • getRows

      public int getRows()

      Return the number of rows to be displayed, or zero for all remaining rows in the table. The default value of this property is zero.

    • setRows

      public void setRows(int rows)

      Set the number of rows to be displayed, or zero for all remaining rows in the table.

      Parameters:
      rows - New number of rows
      Throws:
      IllegalArgumentException - if rows is negative

    • getVar

      public String getVar()

      Return the request-scope attribute under which the data object for the current row will be exposed when iterating. This property is not enabled for value binding expressions.

    • setVar

      public void setVar(String var)

      Set the request-scope attribute under which the data object for the current row wil be exposed when iterating.

      Parameters:
      var - The new request-scope attribute name

    • isRowStatePreserved

      public boolean isRowStatePreserved()

      Return the value of the rowStatePreserved JavaBeans property. See setRowStatePreserved(boolean).

      Since:
      2.1

    • setRowStatePreserved

      public void setRowStatePreserved(boolean preserveComponentState)

      If this property is set to true, the UIData must take steps to ensure that modifications to its iterated children will be preserved on a per-row basis. This allows applications to modify component properties, such as the style-class, for a specific row, rather than having such modifications apply to all rows.

      To accomplish this, UIData must call StateHolder.saveState(javax.faces.context.FacesContext) and TransientStateHolder.saveTransientState(javax.faces.context.FacesContext) on its children to capture their state on exiting each row. When re-entering the row, StateHolder.restoreState(javax.faces.context.FacesContext, java.lang.Object) and TransientStateHolder.restoreTransientState(javax.faces.context.FacesContext, java.lang.Object) must be called in order to reinitialize the children to the correct state for the new row. All of this action must take place during the processing of setRowIndex(int).

      Users should consider enabling this feature for cases where it is necessary to modify properties of UIData's children in a row-specific way. Note, however, that row-level state saving/restoring does add overhead. As such, this feature should be used judiciously.

      Since:
      2.1

    • getValue

      public Object getValue()

      Return the value of the UIData. This value must either be be of type DataModel, or a type that can be adapted into a DataModel. UIData will automatically adapt the following types:

      • Arrays
      • java.util.List
      • java.sql.ResultSet
      • javax.servlet.jsp.jstl.sql.Result
      • java.util.Collection

      All other types will be adapted using the ScalarDataModel class, which will treat the object as a single row of data.

    • setValue

      public void setValue(Object value)

      Set the value of the UIData. This value must either be be of type DataModel, or a type that can be adapted into a DataModel.

      Parameters:
      value - the new value

    • setValueBinding

      public void setValueBinding(String name, ValueBinding binding)
      Deprecated.
      This has been replaced by setValueExpression(java.lang.String, javax.el.ValueExpression).

      If "name" is something other than "value", "var", or "rowIndex", rely on the superclass conversion from ValueBinding to ValueExpression.

      Overrides:
      setValueBinding in class UIComponentBase
      Parameters:
      name - Name of the attribute or property for which to set a ValueBinding
      binding - The ValueBinding to set, or null to remove any currently set ValueBinding
      Throws:
      IllegalArgumentException - if name is one of id, parent, var, or rowIndex
      NullPointerException - if name is null

    • setValueExpression

      public void setValueExpression(String name, ValueExpression binding)

      Set the ValueExpression used to calculate the value for the specified attribute or property name, if any. In addition, if a ValueExpression is set for the value property, remove any synthesized DataModel for the data previously bound to this component.

      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:
      IllegalArgumentException - if name is one of id, parent, var, or rowIndex
      NullPointerException - if name is null
      Since:
      1.2

    • getClientId

      public String getClientId(FacesContext context)

      Return a client identifier for this component that includes the current value of the rowIndex property, if it is not set to -1. This implies that multiple calls to getClientId() may return different results, but ensures that child components can themselves generate row-specific client identifiers (since UIData is a NamingContainer).

      Overrides:
      getClientId in class UIComponentBase
      Parameters:
      context - The FacesContext for the current request
      Throws:
      NullPointerException - if context is null

    • invokeOnComponent

      public boolean invokeOnComponent(FacesContext context, String clientId, ContextCallback callback) throws FacesException

      Override behavior from UIComponentBase.invokeOnComponent(javax.faces.context.FacesContext, java.lang.String, javax.faces.component.ContextCallback) to provide special care for positioning the data properly before finding the component and invoking the callback on it. If the argument clientId is equal to this.getClientId() simply invoke the contextCallback, passing the context argument and this as arguments, and return true. If the argument clientId is not equal to this.getClientId(), inspect each of the facet children of this UIData instance and for each one, compare its clientId with the argument clientId. If there is a match, invoke the contextCallback, passing the context argument and this as arguments, and return true. Otherwise, attempt to extract a rowIndex from the clientId. For example, if the argument clientId was form:data:3:customerHeader the rowIndex would be 3. Let this value be called newIndex. The current rowIndex of this instance must be saved aside and restored before returning in all cases, regardless of the outcome of the search or if any exceptions are thrown in the process.

      The implementation of this method must never return true if setting the rowIndex of this instance to be equal to newIndex causes this instance to return false from isRowAvailable().

      Overrides:
      invokeOnComponent in class UIComponentBase
      Parameters:
      context - the FacesContext for the current request
      clientId - the client identifier of the component to be passed to the argument callback.
      callback - an implementation of the Callback interface.
      Returns:
      true if the a component with the given clientId is found, the callback method was successfully invoked passing that component as an argument, and no Exception was thrown. Returns false if no component with the given clientId is found.
      Throws:
      NullPointerException - if any of the arguments are null
      FacesException - if the argument Callback throws an Exception, it is wrapped in a FacesException and re-thrown. Also throws FacesException if any exception is thrown when deriving the rowIndex from the argument clientId.
      Since:
      1.2

    • queueEvent

      public void queueEvent(FacesEvent event)

      Override the default UIComponentBase.queueEvent(javax.faces.event.FacesEvent) processing to wrap any queued events in a wrapper so that we can reset the current row index in broadcast().

      Overrides:
      queueEvent in class UIComponentBase
      Parameters:
      event - FacesEvent to be queued
      Throws:
      IllegalStateException - if this component is not a descendant of a UIViewRoot
      NullPointerException - if event is null

    • broadcast

      public void broadcast(FacesEvent event) throws AbortProcessingException

      Override the default UIComponentBase.broadcast(javax.faces.event.FacesEvent) processing to unwrap any wrapped FacesEvent and reset the current row index, before the event is actually broadcast. For events that we did not wrap (in queueEvent()), default processing will occur.

      Overrides:
      broadcast in class UIComponentBase
      Parameters:
      event - The FacesEvent to be broadcast
      Throws:
      AbortProcessingException - Signal the JavaServer Faces implementation that no further processing on the current event should be performed
      IllegalArgumentException - if the implementation class of this FacesEvent is not supported by this component
      NullPointerException - if event is null

    • encodeBegin

      public void encodeBegin(FacesContext context) throws IOException

      In addition to the default behavior, ensure that any saved per-row state for our child input components is discarded unless it is needed to rerender the current page with errors.

      Overrides:
      encodeBegin in class UIComponentBase
      Parameters:
      context - FacesContext for the current request
      Throws:
      IOException - if an input/output error occurs while rendering
      NullPointerException - if context is null

    • processDecodes

      public void processDecodes(FacesContext context)

      Override the default UIComponentBase.processDecodes(javax.faces.context.FacesContext) processing to perform the following steps.

      • If the rendered property of this UIComponent is false, skip further processing.
      • Set the current rowIndex to -1.
      • Call the processDecodes() method of all facets of this UIData, in the order determined by a call to getFacets().keySet().iterator().
      • Call the processDecodes() method of all facets of the UIColumn children of this UIData.
      • Iterate over the set of rows that were included when this component was rendered (i.e. those defined by the first and rows properties), performing the following processing for each row:
        • Set the current rowIndex to the appropriate value for this row.
        • If isRowAvailable() returns true, iterate over the children components of each UIColumn child of this UIData component, calling the processDecodes() method for each such child.
      • Set the current rowIndex to -1.
      • Call the decode() method of this component.
      • If a RuntimeException is thrown during decode processing, call FacesContext.renderResponse() and re-throw the exception.
      Overrides:
      processDecodes in class UIComponentBase
      Parameters:
      context - FacesContext for the current request
      Throws:
      NullPointerException - if context is null

    • processValidators

      public void processValidators(FacesContext context)

      Override the default UIComponentBase.processValidators(javax.faces.context.FacesContext) processing to perform the following steps.

      • If the rendered property of this UIComponent is false, skip further processing.
      • Set the current rowIndex to -1.
      • Call the processValidators() method of all facets of this UIData, in the order determined by a call to getFacets().keySet().iterator().
      • Call the processValidators() method of all facets of the UIColumn children of this UIData.
      • Iterate over the set of rows that were included when this component was rendered (i.e. those defined by the first and rows properties), performing the following processing for each row:
        • Set the current rowIndex to the appropriate value for this row.
        • If isRowAvailable() returns true, iterate over the children components of each UIColumn child of this UIData component, calling the processValidators() method for each such child.
      • Set the current rowIndex to -1.
      Overrides:
      processValidators in class UIComponentBase
      Parameters:
      context - FacesContext for the current request
      Throws:
      NullPointerException - if context is null

    • processUpdates

      public void processUpdates(FacesContext context)

      Override the default UIComponentBase.processUpdates(javax.faces.context.FacesContext) processing to perform the following steps.

      • If the rendered property of this UIComponent is false, skip further processing.
      • Set the current rowIndex to -1.
      • Call the processUpdates() method of all facets of this UIData, in the order determined by a call to getFacets().keySet().iterator().
      • Call the processUpdates() method of all facets of the UIColumn children of this UIData.
      • Iterate over the set of rows that were included when this component was rendered (i.e. those defined by the first and rows properties), performing the following processing for each row:
        • Set the current rowIndex to the appropriate value for this row.
        • If isRowAvailable() returns true, iterate over the children components of each UIColumn child of this UIData component, calling the processUpdates() method for each such child.
      • Set the current rowIndex to -1.
      Overrides:
      processUpdates in class UIComponentBase
      Parameters:
      context - FacesContext for the current request
      Throws:
      NullPointerException - if context is null

    • createUniqueId

      public String createUniqueId(FacesContext context, String seed)
      Description copied from interface: UniqueIdVendor

      Generate an identifier for a component. The identifier will be prefixed with UNIQUE_ID_PREFIX, and will be unique within this component-container. Optionally, a unique seed value can be supplied by component creators which should be included in the generated unique id.

      Specified by:
      createUniqueId in interface UniqueIdVendor
      Parameters:
      context - FacesContext
      seed - an optional seed value - e.g. based on the position of the component in the VDL-template
      Returns:
      a unique-id in this component-container

    • visitTree

      public boolean visitTree(VisitContext context, VisitCallback callback)

      Override the behavior in UIComponent.visitTree(javax.faces.component.visit.VisitContext, javax.faces.component.visit.VisitCallback) to handle iteration correctly.

      If the UIComponent.isVisitable(javax.faces.component.visit.VisitContext) method of this instance returns false, take no action and return.

      Call UIComponent.pushComponentToEL(javax.faces.context.FacesContext, javax.faces.component.UIComponent) and invoke the visit callback on this UIData instance as described in UIComponent.visitTree(javax.faces.component.visit.VisitContext, javax.faces.component.visit.VisitCallback). Let the result of the invoctaion be visitResult. If visitResult is VisitResult.COMPLETE, take no further action and return true. Otherwise, determine if we need to visit our children. The default implementation calls VisitContext.getSubtreeIdsToVisit(javax.faces.component.UIComponent) passing this as the argument. If the result of that call is non-empty, let doVisitChildren be true. If doVisitChildren is true and visitResult is VisitResult.ACCEPT, take the following action.

      Call UIComponent.popComponentFromEL(javax.faces.context.FacesContext) and restore the saved row index with a call to setRowIndex(int).

      Return false to allow the visiting to continue.

      Overrides:
      visitTree in class UIComponent
      Parameters:
      context - the VisitContext that provides context for performing the visit.
      callback - the callback to be invoked for each node encountered in the visit.
      Returns:
      component implementations may return true to indicate that the tree visit is complete (eg. all components that need to be visited have been visited). This results in the tree visit being short-circuited such that no more components are visited.