/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package javax.faces.component;
  
  import java.io.IOException;
  import java.sql.ResultSet;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  import javax.el.ValueExpression;
  import javax.faces.FacesException;
  import javax.faces.application.FacesMessage;
  import javax.faces.component.visit.VisitCallback;
  import javax.faces.component.visit.VisitContext;
  import javax.faces.component.visit.VisitResult;
  import javax.faces.context.ExternalContext;
  import javax.faces.context.FacesContext;
  import javax.faces.event.AbortProcessingException;
  import javax.faces.event.FacesEvent;
  import javax.faces.event.FacesListener;
  import javax.faces.event.PhaseId;
  import javax.faces.event.PostValidateEvent;
  import javax.faces.event.PreValidateEvent;
  import javax.faces.model.ArrayDataModel;
  import javax.faces.model.DataModel;
  import javax.faces.model.ListDataModel;
  import javax.faces.model.ResultDataModel;
  import javax.faces.model.ResultSetDataModel;
  import javax.faces.model.ScalarDataModel;
  import javax.servlet.jsp.jstl.sql.Result;
  
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFComponent;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFFacet;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;
  
  /**
   * Represents an abstraction of a component which has multiple "rows" of data.
   * <p>
   * The children of this component are expected to be UIColumn components.
   * <p>
   * Note that the same set of child components are reused to implement each row of the table in turn during such phases
   * as apply-request-values and render-response. Altering any of the members of these components therefore affects the
   * attribute for every row, except for the following members:
   * <ul>
   * <li>submittedValue
   * <li>value (where no EL binding is used)
   * <li>valid
   * </ul>
   * <p>
   * This reuse of the child components also means that it is not possible to save a reference to a component during table
   * processing, then access it later and expect it to still represent the same row of the table.
   * <h1>
   * Implementation Notes</h1>
   * <p>
   * Each of the UIColumn children of this component has a few component children of its own to render the contents of the
   * table cell. However there can be a very large number of rows in a table, so it isn't efficient for the UIColumn and
   * all its child objects to be duplicated for each row in the table. Instead the "flyweight" pattern is used where a
   * serialized state is held for each row. When setRowIndex is invoked, the UIColumn objects and their children serialize
   * their current state then reinitialise themselves from the appropriate saved state. This allows a single set of real
   * objects to represent multiple objects which have the same types but potentially different internal state. When a row
   * is selected for the first time, its state is set to a clean "initial" state. Transient components (including any
   * read-only component) do not save their state; they are just reinitialised as required. The state saved/restored when
   * changing rows is not the complete component state, just the fields that are expected to vary between rows:
   * "submittedValue", "value", "isValid".
   * </p>
   * <p>
   * Note that a table is a "naming container", so that components within the table have their ids prefixed with the id of
   * the table. Actually, when setRowIndex has been called on a table with id of "zzz" the table pretends to its children
   * that its ID is "zzz_n" where n is the row index. This means that renderers for child components which call
   * component.getClientId automatically get ids of form "zzz_n:childId" thus ensuring that components in different rows
   * of the table get different ids.
   * </p>
   * <p>
   * When decoding a submitted page, this class iterates over all its possible rowIndex values, restoring the appropriate
   * serialized row state then calling processDecodes on the child components. Because the child components (or their
   * renderers) use getClientId to get the request key to look for parameter data, and because this object pretends to
   * have a different id per row ("zzz_n") a single child component can decode data from each table row in turn without
   * being aware that it is within a table. The table's data model is updated before each call to child.processDecodes, so
  * the child decode method can assume that the data model's rowData points to the model object associated with the row
  * currently being decoded. Exactly the same process applies for the later validation and updateModel phases.
  * </p>
  * <p>
  * When the data model for the table is bound to a backing bean property, and no validation errors have occured during
  * processing of a postback, the data model is refetched at the start of the rendering phase (ie after the update model
  * phase) so that the contents of the data model can be changed as a result of the latest form submission. Because the
  * saved row state must correspond to the elements within the data model, the row state must be discarded whenever a new
  * data model is fetched; not doing this would cause all sorts of inconsistency issues. This does imply that changing
  * the state of any of the members "submittedValue", "value" or "valid" of a component within the table during the
  * invokeApplication phase has no effect on the rendering of the table. When a validation error has occurred, a new
  * DataModel is <i>not</i> fetched, and the saved state of the child components is <i>not</i> discarded.
  * </p>
  * see Javadoc of the <a href="http://java.sun.com/j2ee/javaserverfaces/1.2/docs/api/index.html">JSF Specification</a>
  * for more information.
  * 
  * @author Manfred Geiler (latest modification by $Author: lu4242 $)
  * @version $Revision: 1470767 $ $Date: 2013-04-22 20:07:29 -0500 (Mon, 22 Apr 2013) $
  */
 @JSFComponent(defaultRendererType = "javax.faces.Table")
 public class UIData extends UIComponentBase implements NamingContainer, UniqueIdVendor
 {
     public static final String COMPONENT_FAMILY = "javax.faces.Data";
     public static final String COMPONENT_TYPE = "javax.faces.Data"; // for unit tests
 
     private static final String FOOTER_FACET_NAME = "footer";
     private static final String HEADER_FACET_NAME = "header";
     private static final Class<Object[]> OBJECT_ARRAY_CLASS = Object[].class;
     private static final int PROCESS_DECODES = 1;
     private static final int PROCESS_VALIDATORS = 2;
     private static final int PROCESS_UPDATES = 3;
     private static final String SKIP_ITERATION_HINT = "javax.faces.visit.SKIP_ITERATION";
 
     private static final Object[] LEAF_NO_STATE = new Object[]{null,null};
 
     private int _rowIndex = -1;
 
     // Holds for each row the states of the child components of this UIData.
     // Note that only "partial" component state is saved: the component fields
     // that are expected to vary between rows.
     private Map<String, Collection<Object[]>> _rowStates = new HashMap<String, Collection<Object[]>>();
 
     /**
      * Handle case where this table is nested inside another table. See method getDataModel for more details.
      * <p>
      * Key: parentClientId (aka rowId when nested within a parent table) Value: DataModel
      */
     private Map<String, DataModel> _dataModelMap = new HashMap<String, DataModel>();
 
     // will be set to false if the data should not be refreshed at the beginning of the encode phase
     private boolean _isValidChilds = true;
 
     private Object _initialDescendantComponentState = null;
 
     //private int _first;
     //private boolean _firstSet;
     //private int _rows;
     //private boolean _rowsSet;
     //private Object _value;
 
     private static class FacesEventWrapper extends FacesEvent
     {
         private static final long serialVersionUID = 6648047974065628773L;
         private FacesEvent _wrappedFacesEvent;
         private int _rowIndex;
 
         public FacesEventWrapper(FacesEvent facesEvent, int rowIndex, UIData redirectComponent)
         {
             super(redirectComponent);
             _wrappedFacesEvent = facesEvent;
             _rowIndex = rowIndex;
         }
 
         @Override
         public PhaseId getPhaseId()
         {
             return _wrappedFacesEvent.getPhaseId();
         }
 
         @Override
         public void setPhaseId(PhaseId phaseId)
         {
             _wrappedFacesEvent.setPhaseId(phaseId);
         }
 
         @Override
         public void queue()
         {
             _wrappedFacesEvent.queue();
         }
 
         @Override
         public String toString()
         {
             return _wrappedFacesEvent.toString();
         }
 
         @Override
         public boolean isAppropriateListener(FacesListener faceslistener)
         {
             return _wrappedFacesEvent.isAppropriateListener(faceslistener);
         }
 
         @Override
         public void processListener(FacesListener faceslistener)
         {
             _wrappedFacesEvent.processListener(faceslistener);
         }
 
         public FacesEvent getWrappedFacesEvent()
         {
             return _wrappedFacesEvent;
         }
 
         public int getRowIndex()
         {
             return _rowIndex;
         }
     }
 
     private static final DataModel EMPTY_DATA_MODEL = new DataModel()
     {
         @Override
         public boolean isRowAvailable()
         {
             return false;
         }
 
         @Override
         public int getRowCount()
         {
             return 0;
         }
 
         @Override
         public Object getRowData()
         {
             throw new IllegalArgumentException();
         }
 
         @Override
         public int getRowIndex()
         {
             return -1;
         }
 
         @Override
         public void setRowIndex(int i)
         {
             if (i < -1)
             {
                 throw new IllegalArgumentException();
             }
         }
 
         @Override
         public Object getWrappedData()
         {
             return null;
         }
 
         @Override
         public void setWrappedData(Object obj)
         {
             if (obj == null)
             {
                 return; // Clearing is allowed
             }
             throw new UnsupportedOperationException(this.getClass().getName() + " UnsupportedOperationException");
         }
     };
 
     private class EditableValueHolderState
     {
         private final Object _value;
         private final boolean _localValueSet;
         private final boolean _valid;
         private final Object _submittedValue;
 
         public EditableValueHolderState(EditableValueHolder evh)
         {
             _value = evh.getLocalValue();
             _localValueSet = evh.isLocalValueSet();
             _valid = evh.isValid();
             _submittedValue = evh.getSubmittedValue();
         }
 
         public void restoreState(EditableValueHolder evh)
         {
             evh.setValue(_value);
             evh.setLocalValueSet(_localValueSet);
             evh.setValid(_valid);
             evh.setSubmittedValue(_submittedValue);
         }
     }
 
     /**
      * Construct an instance of the UIData.
      */
     public UIData()
     {
         setRendererType("javax.faces.Table");
     }
 
     @Override
     public boolean invokeOnComponent(FacesContext context, String clientId, ContextCallback callback)
         throws FacesException
     {
         if (context == null || clientId == null || callback == null)
         {
             throw new NullPointerException();
         }
         
         final String baseClientId = getClientId(context);
 
         // searching for this component?
         boolean returnValue = baseClientId.equals(clientId);
 
         boolean isCachedFacesContext = isCachedFacesContext();
         if (!isCachedFacesContext)
         {
             setCachedFacesContext(context);
         }
         
         pushComponentToEL(context, this);
         try
         {
             if (returnValue)
             {
                 try
                 {
                     callback.invokeContextCallback(context, this);
                     return true;
                 }
                 catch (Exception e)
                 {
                     throw new FacesException(e);
                 }
             }
     
             // Now Look throught facets on this UIComponent
             if (this.getFacetCount() > 0)
             {
                 for (Iterator<UIComponent> it = this.getFacets().values().iterator(); !returnValue && it.hasNext();)
                 {
                     returnValue = it.next().invokeOnComponent(context, clientId, callback);
                 }
             }
     
             if (returnValue)
             {
                 return returnValue;
             }
             
             // is the component an inner component?
             if (clientId.startsWith(baseClientId))
             {
                 // Check if the clientId for the component, which we 
                 // are looking for, has a rowIndex attached
                 char separator = UINamingContainer.getSeparatorChar(context);
                 String subId = clientId.substring(baseClientId.length() + 1);
                 //If the char next to baseClientId is the separator one and
                 //the subId matches the regular expression
                 if (clientId.charAt(baseClientId.length()) == separator && 
                         subId.matches("[0-9]+"+separator+".*"))
                 {
                     String clientRow = subId.substring(0, subId.indexOf(separator));
         
                     //Now we save the current position
                     int oldRow = this.getRowIndex();
                     
                     // try-finally --> make sure, that the old row index is restored
                     try
                     {
                         //The conversion is safe, because its already checked on the
                         //regular expresion
                         this.setRowIndex(Integer.parseInt(clientRow));
                         
                         // check, if the row is available
                         if (!isRowAvailable())
                         {
                             return false;
                         }
             
                         for (Iterator<UIComponent> it1 = getChildren().iterator(); 
                                 !returnValue && it1.hasNext();)
                         {
                             //recursive call to find the component
                             returnValue = it1.next().invokeOnComponent(context, clientId, callback);
                         }
                     }
                     finally
                     {
                         //Restore the old position. Doing this prevent
                         //side effects.
                         this.setRowIndex(oldRow);
                     }
                 }
                 else
                 {
                     // MYFACES-2370: search the component in the childrens' facets too.
                     // We have to check the childrens' facets here, because in MyFaces
                     // the rowIndex is not attached to the clientId for the children of
                     // facets of the UIColumns. However, in RI the rowIndex is 
                     // attached to the clientId of UIColumns' Facets' children.
                     for (Iterator<UIComponent> itChildren = this.getChildren().iterator();
                             !returnValue && itChildren.hasNext();)
                     {
                         UIComponent child = itChildren.next();
                         if (child instanceof UIColumn && clientId.equals(child.getClientId(context)))
                         {
                             try
                             {
                                 callback.invokeContextCallback(context, child);
                             }
                             catch (Exception e)
                             {
                                 throw new FacesException(e);
                             }
                             returnValue = true;
                         }
                         // process the child's facets
                         if (child.getFacetCount() > 0)
                         {
                             for (Iterator<UIComponent> itChildFacets = 
                                 child.getFacets().values().iterator(); 
                                 !returnValue && itChildFacets.hasNext();)
                             {
                                 //recursive call to find the component
                                 returnValue = itChildFacets.next().invokeOnComponent(
                                     context, clientId, callback);
                             }
                         }
                     }
                 }
             }
         }
         finally
         {
             //all components must call popComponentFromEl after visiting is finished
             popComponentFromEL(context);
             if (!isCachedFacesContext)
             {
                 setCachedFacesContext(null);
             }
         }
 
         return returnValue;
     }
 
     public void setFooter(UIComponent footer)
     {
         getFacets().put(FOOTER_FACET_NAME, footer);
     }
 
     @JSFFacet
     public UIComponent getFooter()
     {
         return getFacets().get(FOOTER_FACET_NAME);
     }
 
     public void setHeader(UIComponent header)
     {
         getFacets().put(HEADER_FACET_NAME, header);
     }
 
     @JSFFacet
     public UIComponent getHeader()
     {
         return getFacets().get(HEADER_FACET_NAME);
     }
 
     public boolean isRowAvailable()
     {
         return getDataModel().isRowAvailable();
     }
 
     public int getRowCount()
     {
         return getDataModel().getRowCount();
     }
 
     public Object getRowData()
     {
         return getDataModel().getRowData();
     }
 
     public int getRowIndex()
     {
         return _rowIndex;
     }
 
     /**
      * Set the current row index that methods like getRowData use.
      * <p>
      * Param rowIndex can be -1, meaning "no row".
      * <p>
      * 
      * @param rowIndex
      */
     public void setRowIndex(int rowIndex)
     {
         if (rowIndex < -1)
         {
             throw new IllegalArgumentException("rowIndex is less than -1");
         }
 
         if (_rowIndex == rowIndex)
         {
             return;
         }
 
         FacesContext facesContext = getFacesContext();
 
         if (_rowIndex == -1)
         {
             if (_initialDescendantComponentState == null)
             {
                 // Create a template that can be used to initialise any row
                 // that we haven't visited before, ie a "saved state" that can
                 // be pushed to the "restoreState" method of all the child
                 // components to set them up to represent a clean row.
                 _initialDescendantComponentState = saveDescendantComponentStates(this, false, false);
             }
         }
         else
         {
             // If no initial component state, there are no EditableValueHolder instances,
             // and that means there is no state to be saved for the current row, so we can
             // skip row state saving code safely.
             if (_initialDescendantComponentState != null)
             {
                 // We are currently positioned on some row, and are about to
                 // move off it, so save the (partial) state of the components
                 // representing the current row. Later if this row is revisited
                 // then we can restore this state.
                 Collection<Object[]> savedRowState = saveDescendantComponentStates(this, false, false);
                 if (savedRowState != null)
                 {
                     _rowStates.put(getContainerClientId(facesContext), savedRowState);
                 }
             }
         }
 
         _rowIndex = rowIndex;
 
         DataModel dataModel = getDataModel();
         dataModel.setRowIndex(rowIndex);
 
         String var = (String) getStateHelper().get(PropertyKeys.var);
         if (rowIndex == -1)
         {
             if (var != null)
             {
                 facesContext.getExternalContext().getRequestMap().remove(var);
             }
         }
         else
         {
             if (var != null)
             {
                 if (isRowAvailable())
                 {
                     Object rowData = dataModel.getRowData();
                     facesContext.getExternalContext().getRequestMap().put(var, rowData);
                 }
                 else
                 {
                     facesContext.getExternalContext().getRequestMap().remove(var);
                 }
             }
         }
 
         if (_rowIndex == -1)
         {
             // reset components to initial state
             // If no initial state, skip row restore state code
             if (_initialDescendantComponentState != null)
             {
                 restoreDescendantComponentStates(this, false, _initialDescendantComponentState, false);
             }
             else
             {
                 restoreDescendantComponentWithoutRestoreState(this, false, false);
             }
         }
         else
         {
             Object rowState = _rowStates.get(getContainerClientId(facesContext));
             if (rowState == null)
             {
                 // We haven't been positioned on this row before, so just
                 // configure the child components of this component with
                 // the standard "initial" state
                 // If no initial state, skip row restore state code
                 if (_initialDescendantComponentState != null)
                 {
                     restoreDescendantComponentStates(this, false, _initialDescendantComponentState, false);
                 }
                 else
                 {
                     restoreDescendantComponentWithoutRestoreState(this, false, false);
                 }
             }
             else
             {
                 // We have been positioned on this row before, so configure
                 // the child components of this component with the (partial)
                 // state that was previously saved. Fields not in the
                 // partial saved state are left with their original values.
                 restoreDescendantComponentStates(this, false, rowState, false);
             }
         }
     }
 
     /**
      * Overwrite the state of the child components of this component with data previously saved by method
      * saveDescendantComponentStates.
      * <p>
      * The saved state info only covers those fields that are expected to vary between rows of a table. Other fields are
      * not modified.
      */
     @SuppressWarnings("unchecked")
     private void restoreDescendantComponentStates(UIComponent parent, boolean iterateFacets, Object state,
                                                   boolean restoreChildFacets)
     {
         int descendantStateIndex = -1;
         List<? extends Object[]> stateCollection = null;
         
         if (iterateFacets && parent.getFacetCount() > 0)
         {
             Iterator<UIComponent> childIterator = parent.getFacets().values().iterator();
             
             while (childIterator.hasNext())
             {
                 UIComponent component = childIterator.next();
 
                 // reset the client id (see spec 3.1.6)
                 component.setId(component.getId());
                 if (!component.isTransient())
                 {
                     if (descendantStateIndex == -1)
                     {
                         stateCollection = ((List<? extends Object[]>) state);
                         descendantStateIndex = stateCollection.isEmpty() ? -1 : 0;
                     }
                     
                     if (descendantStateIndex != -1 && descendantStateIndex < stateCollection.size())
                     {
                         Object[] object = stateCollection.get(descendantStateIndex);
                         if (object[0] != null && component instanceof EditableValueHolder)
                         {
                             ((EditableValueHolderState) object[0]).restoreState((EditableValueHolder) component);
                         }
                         // If there is descendant state to restore, call it recursively, otherwise
                         // it is safe to skip iteration.
                         if (object[1] != null)
                         {
                             restoreDescendantComponentStates(component, restoreChildFacets, object[1], true);
                         }
                         else
                         {
                             restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                         }
                     }
                     else
                     {
                         restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                     }
                     descendantStateIndex++;
                 }
             }
         }
         
         if (parent.getChildCount() > 0)
         {
             for (int i = 0; i < parent.getChildCount(); i++)
             {
                 UIComponent component = parent.getChildren().get(i);
 
                 // reset the client id (see spec 3.1.6)
                 component.setId(component.getId());
                 if (!component.isTransient())
                 {
                     if (descendantStateIndex == -1)
                     {
                         stateCollection = ((List<? extends Object[]>) state);
                         descendantStateIndex = stateCollection.isEmpty() ? -1 : 0;
                     }
                     
                     if (descendantStateIndex != -1 && descendantStateIndex < stateCollection.size())
                     {
                         Object[] object = stateCollection.get(descendantStateIndex);
                         if (object[0] != null && component instanceof EditableValueHolder)
                         {
                             ((EditableValueHolderState) object[0]).restoreState((EditableValueHolder) component);
                         }
                         // If there is descendant state to restore, call it recursively, otherwise
                         // it is safe to skip iteration.
                         if (object[1] != null)
                         {
                             restoreDescendantComponentStates(component, restoreChildFacets, object[1], true);
                         }
                         else
                         {
                             restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                         }
                     }
                     else
                     {
                         restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                     }
                     descendantStateIndex++;
                 }
             }
         }
     }
 
     /**
      * Just call component.setId(component.getId()) to reset all client ids and 
      * ensure they will be calculated for the current row, but do not waste time
      * dealing with row state code.
      * 
      * @param parent
      * @param iterateFacets
      * @param restoreChildFacets 
      */
     private void restoreDescendantComponentWithoutRestoreState(UIComponent parent, boolean iterateFacets,
                                                                boolean restoreChildFacets)
     {
         if (iterateFacets && parent.getFacetCount() > 0)
         {
             Iterator<UIComponent> childIterator = parent.getFacets().values().iterator();
             
             while (childIterator.hasNext())
             {
                 UIComponent component = childIterator.next();
 
                 // reset the client id (see spec 3.1.6)
                 component.setId(component.getId());
                 if (!component.isTransient())
                 {
                     restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                 }
             }
         }
         
         if (parent.getChildCount() > 0)
         {
             for (int i = 0; i < parent.getChildCount(); i++)
             {
                 UIComponent component = parent.getChildren().get(i);
 
                 // reset the client id (see spec 3.1.6)
                 component.setId(component.getId());
                 if (!component.isTransient())
                 {
                     restoreDescendantComponentWithoutRestoreState(component, restoreChildFacets, true);
                 }
             }
         }
     }
 
     /**
      * Walk the tree of child components of this UIData, saving the parts of their state that can vary between rows.
      * <p>
      * This is very similar to the process that occurs for normal components when the view is serialized. Transient
      * components are skipped (no state is saved for them).
      * <p>
      * If there are no children then null is returned. If there are one or more children, and all children are transient
      * then an empty collection is returned; this will happen whenever a table contains only read-only components.
      * <p>
      * Otherwise a collection is returned which contains an object for every non-transient child component; that object
      * may itself contain a collection of the state of that child's child components.
      */
     private Collection<Object[]> saveDescendantComponentStates(UIComponent parent, boolean iterateFacets,
                                                                boolean saveChildFacets)
     {
         Collection<Object[]> childStates = null;
         // Index to indicate how many components has been passed without state to save.
         int childEmptyIndex = 0;
         int totalChildCount = 0;
                 
         if (iterateFacets && parent.getFacetCount() > 0)
         {
             Iterator<UIComponent> childIterator = parent.getFacets().values().iterator();
 
             while (childIterator.hasNext())
             {
                 UIComponent child = childIterator.next();
                 if (!child.isTransient())
                 {
                     // Add an entry to the collection, being an array of two
                     // elements. The first element is the state of the children
                     // of this component; the second is the state of the current
                     // child itself.
 
                     if (child instanceof EditableValueHolder)
                     {
                         if (childStates == null)
                         {
                             childStates = new ArrayList<Object[]>(
                                     parent.getFacetCount()
                                     + parent.getChildCount()
                                     - totalChildCount
                                     + childEmptyIndex);
                             for (int ci = 0; ci < childEmptyIndex; ci++)
                             {
                                 childStates.add(LEAF_NO_STATE);
                             }
                         }
                     
                         childStates.add(child.getChildCount() > 0 ? 
                                 new Object[]{new EditableValueHolderState((EditableValueHolder) child),
                                     saveDescendantComponentStates(child, saveChildFacets, true)} :
                                 new Object[]{new EditableValueHolderState((EditableValueHolder) child),
                                     null});
                     }
                     else if (child.getChildCount() > 0 || (saveChildFacets && child.getFacetCount() > 0))
                     {
                         Object descendantSavedState = saveDescendantComponentStates(child, saveChildFacets, true);
                         
                         if (descendantSavedState == null)
                         {
                             if (childStates == null)
                             {
                                 childEmptyIndex++;
                             }
                             else
                             {
                                 childStates.add(LEAF_NO_STATE);
                             }
                         }
                         else
                         {
                             if (childStates == null)
                             {
                                 childStates = new ArrayList<Object[]>(
                                         parent.getFacetCount()
                                         + parent.getChildCount()
                                         - totalChildCount
                                         + childEmptyIndex);
                                 for (int ci = 0; ci < childEmptyIndex; ci++)
                                 {
                                     childStates.add(LEAF_NO_STATE);
                                 }
                             }
                             childStates.add(new Object[]{null, descendantSavedState});
                         }
                     }
                     else
                     {
                         if (childStates == null)
                         {
                             childEmptyIndex++;
                         }
                         else
                         {
                             childStates.add(LEAF_NO_STATE);
                         }
                     }
                 }
                 totalChildCount++;
             }
         }
         
         if (parent.getChildCount() > 0)
         {
             for (int i = 0; i < parent.getChildCount(); i++)
             {
                 UIComponent child = parent.getChildren().get(i);
                 if (!child.isTransient())
                 {
                     // Add an entry to the collection, being an array of two
                     // elements. The first element is the state of the children
                     // of this component; the second is the state of the current
                     // child itself.
 
                     if (child instanceof EditableValueHolder)
                     {
                         if (childStates == null)
                         {
                             childStates = new ArrayList<Object[]>(
                                     parent.getFacetCount()
                                     + parent.getChildCount()
                                     - totalChildCount
                                     + childEmptyIndex);
                             for (int ci = 0; ci < childEmptyIndex; ci++)
                             {
                                 childStates.add(LEAF_NO_STATE);
                             }
                         }
                     
                         childStates.add(child.getChildCount() > 0 ? 
                                 new Object[]{new EditableValueHolderState((EditableValueHolder) child),
                                     saveDescendantComponentStates(child, saveChildFacets, true)} :
                                 new Object[]{new EditableValueHolderState((EditableValueHolder) child),
                                     null});
                     }
                     else if (child.getChildCount() > 0 || (saveChildFacets && child.getFacetCount() > 0))
                     {
                         Object descendantSavedState = saveDescendantComponentStates(child, saveChildFacets, true);
                         
                         if (descendantSavedState == null)
                         {
                             if (childStates == null)
                             {
                                 childEmptyIndex++;
                             }
                             else
                             {
                                 childStates.add(LEAF_NO_STATE);
                             }
                         }
                         else
                         {
                             if (childStates == null)
                             {
                                 childStates = new ArrayList<Object[]>(
                                         parent.getFacetCount()
                                         + parent.getChildCount()
                                         - totalChildCount
                                         + childEmptyIndex);
                                 for (int ci = 0; ci < childEmptyIndex; ci++)
                                 {
                                     childStates.add(LEAF_NO_STATE);
                                 }
                             }
                             childStates.add(new Object[]{null, descendantSavedState});
                         }
                     }
                     else
                     {
                         if (childStates == null)
                         {
                             childEmptyIndex++;
                         }
                         else
                         {
                             childStates.add(LEAF_NO_STATE);
                         }
                     }
                 }
                 totalChildCount++;
             }
         }
         
         return childStates;
     }
     
     @Override
     public void setValueExpression(String name, ValueExpression binding)
     {
         if (name == null)
         {
             throw new NullPointerException("name");
         }
         else if (name.equals("value"))
         {
             _dataModelMap.clear();
         }
         else if (name.equals("rowIndex"))
         {
             throw new IllegalArgumentException("name " + name);
         }
         super.setValueExpression(name, binding);
     }
 
     /*
     @Override
     public String getClientId(FacesContext context)
     {
         String clientId = super.getClientId(context);
         int rowIndex = getRowIndex();
         if (rowIndex == -1)
         {
             return clientId;
         }
 
         StringBuilder bld = __getSharedStringBuilder();
         return bld.append(clientId).append(UINamingContainer.getSeparatorChar(context)).append(rowIndex).toString();
     }*/
 
     @Override
     public String getContainerClientId(FacesContext context)
     {
         //MYFACES-2744 UIData.getClientId() should not append rowIndex, instead use UIData.getContainerClientId()
         String clientId = super.getContainerClientId(context);
         
         int rowIndex = getRowIndex();
         if (rowIndex == -1)
         {
             return clientId;
         }
 
         StringBuilder bld = __getSharedStringBuilder(context);
         return bld.append(clientId).append(UINamingContainer.getSeparatorChar(context)).append(rowIndex).toString();        
     }
 
     /**
      * Modify events queued for any child components so that the UIData state will be correctly configured before the
      * event's listeners are executed.
      * <p>
      * Child components or their renderers may register events against those child components. When the listener for
      * that event is eventually invoked, it may expect the uidata's rowData and rowIndex to be referring to the same
      * object that caused the event to fire.
      * <p>
      * The original queueEvent call against the child component has been forwarded up the chain of ancestors in the
      * standard way, making it possible here to wrap the event in a new event whose source is <i>this</i> component, not
      * the original one. When the event finally is executed, this component's broadcast method is invoked, which ensures
      * that the UIData is set to be at the correct row before executing the original event.
      */
     @Override
     public void queueEvent(FacesEvent event)
     {
         super.queueEvent(new FacesEventWrapper(event, getRowIndex(), this));
     }
 
     /**
      * Ensure that before the event's listeners are invoked this UIData component's "current row" is set to the row
      * associated with the event.
      * <p>
      * See queueEvent for more details.
      */
     @Override
     public void broadcast(FacesEvent event) throws AbortProcessingException
     {
         if (event instanceof FacesEventWrapper)
         {
             FacesEvent originalEvent = ((FacesEventWrapper) event).getWrappedFacesEvent();
             int eventRowIndex = ((FacesEventWrapper) event).getRowIndex();
             final int currentRowIndex = getRowIndex();
             UIComponent source = originalEvent.getComponent();
             UIComponent compositeParent = UIComponent.getCompositeComponentParent(source);
 
             setRowIndex(eventRowIndex);
             if (compositeParent != null)
             {
                 pushComponentToEL(getFacesContext(), compositeParent);
             }
             pushComponentToEL(getFacesContext(), source);
             try
             {
                 source.broadcast(originalEvent);
             }
             finally
             {
                 source.popComponentFromEL(getFacesContext());
                 if (compositeParent != null)
                 {
                     compositeParent.popComponentFromEL(getFacesContext());
                 }
                 setRowIndex(currentRowIndex);
             }
         }
         else
         {
             super.broadcast(event);
         }
     }
 
     /**
      * 
      * {@inheritDoc}
      * 
      * @since 2.0
      */
     public String createUniqueId(FacesContext context, String seed)
     {
         StringBuilder bld = __getSharedStringBuilder(context);
 
         // Generate an identifier for a component. The identifier will be prefixed with UNIQUE_ID_PREFIX,
         // and will be unique within this UIViewRoot.
         if(seed==null)
         {
             Long uniqueIdCounter = (Long) getStateHelper().get(PropertyKeys.uniqueIdCounter);
             uniqueIdCounter = (uniqueIdCounter == null) ? 0 : uniqueIdCounter;
             getStateHelper().put(PropertyKeys.uniqueIdCounter, (uniqueIdCounter+1L));
             return bld.append(UIViewRoot.UNIQUE_ID_PREFIX).append(uniqueIdCounter).toString();    
         }
         // Optionally, a unique seed value can be supplied by component creators
         // which should be included in the generated unique id.
         else
         {
             return bld.append(UIViewRoot.UNIQUE_ID_PREFIX).append(seed).toString();
         }
     }
 
     /**
      * Perform necessary actions when rendering of this component starts, before delegating to the inherited
      * implementation which calls the associated renderer's encodeBegin method.
      */
     @Override
     public void encodeBegin(FacesContext context) throws IOException
     {
         _initialDescendantComponentState = null;
         if (_isValidChilds && !hasErrorMessages(context))
         {
             // Clear the data model so that when rendering code calls
             // getDataModel a fresh model is fetched from the backing
             // bean via the value-binding.
             _dataModelMap.clear();
 
             // When the data model is cleared it is also necessary to
             // clear the saved row state, as there is an implicit 1:1
             // relation between objects in the _rowStates and the
             // corresponding DataModel element.
             _rowStates.clear();
         }
         super.encodeBegin(context);
     }
 
     private boolean hasErrorMessages(FacesContext context)
     {
         // perf: getMessageList() return a RandomAccess instance.
         // See org.apache.myfaces.context.servlet.FacesContextImpl.addMessage
         List<FacesMessage> messageList = context.getMessageList();
         for (int i = 0, size = messageList.size(); i < size;  i++)
         {
             FacesMessage message = messageList.get(i);
             if (FacesMessage.SEVERITY_ERROR.compareTo(message.getSeverity()) <= 0)
             {
                 return true;
             }
         }
         return false;
     }
 
     /**
      * @see javax.faces.component.UIComponentBase#encodeEnd(javax.faces.context.FacesContext)
      */
     @Override
     public void encodeEnd(FacesContext context) throws IOException
     {
         try
         {
             setCachedFacesContext(context);
             setRowIndex(-1);
         }
         finally
         {
             setCachedFacesContext(null);
         }
         super.encodeEnd(context);
     }
 
     @Override
     public void processDecodes(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
             setRowIndex(-1);
             processFacets(context, PROCESS_DECODES);
             processColumnFacets(context, PROCESS_DECODES);
             processColumnChildren(context, PROCESS_DECODES);
             setRowIndex(-1);
             try
             {
                 decode(context);
             }
             catch (RuntimeException e)
             {
                 context.renderResponse();
                 throw e;
             }
         }
         finally
         {
             popComponentFromEL(context);
             setCachedFacesContext(null);
         }
     }
 
     @Override
     public void processValidators(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
 
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
             
             //Pre validation event dispatch for component
             context.getApplication().publishEvent(context,  PreValidateEvent.class, getClass(), this);
             
             try
             {
                 setRowIndex(-1);
                 processFacets(context, PROCESS_VALIDATORS);
                 processColumnFacets(context, PROCESS_VALIDATORS);
                 processColumnChildren(context, PROCESS_VALIDATORS);
                 setRowIndex(-1);
             }
             finally
             {
                 context.getApplication().publishEvent(context,  PostValidateEvent.class, getClass(), this);
             }
             
             // check if an validation error forces the render response for our data
             if (context.getRenderResponse())
             {
                 _isValidChilds = false;
             }
         }
         finally
         {
             popComponentFromEL(context);
             setCachedFacesContext(null);
         }
     }
 
     @Override
     public void processUpdates(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
             setRowIndex(-1);
             processFacets(context, PROCESS_UPDATES);
             processColumnFacets(context, PROCESS_UPDATES);
             processColumnChildren(context, PROCESS_UPDATES);
             setRowIndex(-1);
     
             if (context.getRenderResponse())
             {
                 _isValidChilds = false;
             }
         }
         finally
         {
             popComponentFromEL(context);
             setCachedFacesContext(null);
         }
     }
 
     private void processFacets(FacesContext context, int processAction)
     {
         if (this.getFacetCount() > 0)
         {
             for (UIComponent facet : getFacets().values())
             {
                 process(context, facet, processAction);
             }
         }
     }
 
     /**
      * Invoke the specified phase on all facets of all UIColumn children of this component. Note that no methods are
      * called on the UIColumn child objects themselves.
      * 
      * @param context
      *            is the current faces context.
      * @param processAction
      *            specifies a JSF phase: decode, validate or update.
      */
     private void processColumnFacets(FacesContext context, int processAction)
     {
         for (int i = 0, childCount = getChildCount(); i < childCount; i++)
         {
             UIComponent child = getChildren().get(i);
             if (child instanceof UIColumn)
             {
                 if (! _ComponentUtils.isRendered(context, child))
                 {
                     // Column is not visible
                     continue;
                 }
                 
                 if (child.getFacetCount() > 0)
                 {
                     for (UIComponent facet : child.getFacets().values())
                     {
                         process(context, facet, processAction);
                     }
                 }
             }
         }
     }
 
     /**
      * Invoke the specified phase on all non-facet children of all UIColumn children of this component. Note that no
      * methods are called on the UIColumn child objects themselves.
      * 
      * @param context
      *            is the current faces context.
      * @param processAction
      *            specifies a JSF phase: decode, validate or update.
      */
     private void processColumnChildren(FacesContext context, int processAction)
     {
         int first = getFirst();
         int rows = getRows();
         int last;
         if (rows == 0)
         {
             last = getRowCount();
         }
         else
         {
             last = first + rows;
         }
         for (int rowIndex = first; last == -1 || rowIndex < last; rowIndex++)
         {
             setRowIndex(rowIndex);
 
             // scrolled past the last row
             if (!isRowAvailable())
             {
                 break;
             }
             
             for (int i = 0, childCount = getChildCount(); i < childCount; i++)
             {
                 UIComponent child = getChildren().get(i);
                 if (child instanceof UIColumn)
                 {
                     if (! _ComponentUtils.isRendered(context, child))
                     {
                         // Column is not visible
                         continue;
                     }
                     for (int j = 0, columnChildCount = child.getChildCount(); j < columnChildCount; j++)
                     {
                         UIComponent columnChild = child.getChildren().get(j);
                         process(context, columnChild, processAction);
                     }
                 }
             }
         }
     }
 
     private void process(FacesContext context, UIComponent component, int processAction)
     {
         switch (processAction)
         {
         case PROCESS_DECODES:
             component.processDecodes(context);
             break;
         case PROCESS_VALIDATORS:
             component.processValidators(context);
             break;
         case PROCESS_UPDATES:
             component.processUpdates(context);
             break;
         }
     }
 
     /**
      * Return the datamodel for this table, potentially fetching the data from a backing bean via a value-binding if
      * this is the first time this method has been called.
      * <p>
      * This is complicated by the fact that this table may be nested within another table. In this case a different
      * datamodel should be fetched for each row. When nested within a parent table, the parent reference won't change
      * but parent.getContainerClientId() will, as the suffix changes
      * depending upon the current row index. A map object on this
      * component is therefore used to cache the datamodel for each row of the table. In the normal case where this table
      * is not nested inside a component that changes its id (like a table does) then this map only ever has one entry.
      */
     protected DataModel getDataModel()
     {
         DataModel dataModel;
         String clientID = "";
 
         UIComponent parent = getParent();
         if (parent != null)
         {
             clientID = parent.getContainerClientId(getFacesContext());
         }
         dataModel = _dataModelMap.get(clientID);
         if (dataModel == null)
         {
             dataModel = createDataModel();
             _dataModelMap.put(clientID, dataModel);
         }
         return dataModel;
     }
 
     protected void setDataModel(DataModel dataModel)
     {
         throw new UnsupportedOperationException("this method is here only to maintain binary compatibility w/ the RI");
     }
 
     /**
      * Evaluate this object's value property and convert the result into a DataModel. Normally this object's value
      * property will be a value-binding which will cause the value to be fetched from some backing bean.
      * <p>
      * The result of fetching the value may be a DataModel object, in which case that object is returned directly. If
      * the value is of type List, Array, ResultSet, Result, other object or null then an appropriate wrapper is created
      * and returned.
      * <p>
      * Null is never returned by this method.
      */
     private DataModel createDataModel()
     {
         Object value = getValue();
 
         if (value == null)
         {
             return EMPTY_DATA_MODEL;
         }
         else if (value instanceof DataModel)
         {
             return (DataModel) value;
         }
         else if (value instanceof List)
         {
             return new ListDataModel((List<?>) value);
         }
         else if (OBJECT_ARRAY_CLASS.isAssignableFrom(value.getClass()))
         {
             return new ArrayDataModel((Object[]) value);
         }
         else if (value instanceof ResultSet)
         {
             return new ResultSetDataModel((ResultSet) value);
         }
         else if (value instanceof Result)
         {
             return new ResultDataModel((Result) value);
         }
         else
         {
             return new ScalarDataModel(value);
         }
     }
 
     /**
      * An EL expression that specifies the data model that backs this table.
      * <p>
      * The value referenced by the EL expression can be of any type.
      * </p>
      * <ul>
      * <li>A value of type DataModel is used directly.</li>
      * <li>Array-like parameters of type array-of-Object, java.util.List, java.sql.ResultSet or
      * javax.servlet.jsp.jstl.sql.Result are wrapped in a corresponding DataModel that knows how to iterate over the
      * elements.</li>
      * <li>Other values are wrapped in a DataModel as a single row.</li>
      * </ul>
      * <p>
      * Note in particular that unordered collections, eg Set are not supported. Therefore if the value expression
      * references such an object then the table will be considered to contain just one element - the collection itself.
      * </p>
      */
     @JSFProperty
     public Object getValue()
     {
         return  getStateHelper().eval(PropertyKeys.value);
     }
 
     public void setValue(Object value)
     {
         getStateHelper().put(PropertyKeys.value, value );
         _dataModelMap.clear();
         _rowStates.clear();
         _isValidChilds = true;
     }
 
     /**
      * Defines the index of the first row to be displayed, starting from 0.
      */
     @JSFProperty
     public int getFirst()
     {
         return (Integer) getStateHelper().eval(PropertyKeys.first,0);
     }
 
     public void setFirst(int first)
     { 
         if (first < 0)
         {
             throw new IllegalArgumentException("Illegal value for first row: " + first);
         }
         getStateHelper().put(PropertyKeys.first, first );
     }
 
     /**
      * Defines the maximum number of rows of data to be displayed.
      * <p>
      * Specify zero to display all rows from the "first" row to the end of available data.
      * </p>
      */
     @JSFProperty
     public int getRows()
     {
         return (Integer) getStateHelper().eval(PropertyKeys.rows,0);
     }
 
     /**
      * Set the maximum number of rows displayed in the table.
      */
     public void setRows(int rows)
     {
         if (rows < 0)
         {
             throw new IllegalArgumentException("rows: " + rows);
         }
         getStateHelper().put(PropertyKeys.rows, rows ); 
     }
 
     /**
      * Defines the name of the request-scope variable that will hold the current row during iteration.
      * <p>
      * During rendering of child components of this UIData, the variable with this name can be read to learn what the
      * "rowData" object for the row currently being rendered is.
      * </p>
      * <p>
      * This value must be a static value, ie an EL expression is not permitted.
      * </p>
      */
     @JSFProperty(literalOnly = true)
     public String getVar()
     {
         return (String) getStateHelper().get(PropertyKeys.var);
     }
 
     /**
      * Overrides the behavior in 
      * UIComponent.visitTree(javax.faces.component.visit.VisitContext, javax.faces.component.visit.VisitCallback)
      * to handle iteration correctly.
      * 
      * @param context the visit context which handles the processing details
      * @param callback the callback to be performed
      * @return false if the processing is not done true if we can shortcut
      * the visiting because we are done with everything
      * 
      * @since 2.0
      */
     @Override
     public boolean visitTree(VisitContext context, VisitCallback callback)
     {
         if (!isVisitable(context))
         {
             return false;
         }
 
         boolean isCachedFacesContext = isCachedFacesContext();
         if (!isCachedFacesContext)
         {
             setCachedFacesContext(context.getFacesContext());
         }
         // save the current row index
         int oldRowIndex = getRowIndex();
         // set row index to -1 to process the facets and to get the rowless clientId
         setRowIndex(-1);
         // push the Component to EL
         pushComponentToEL(context.getFacesContext(), this);
         try
         {
             VisitResult visitResult = context.invokeVisitCallback(this,
                     callback);
             switch (visitResult)
             {
             //we are done nothing has to be processed anymore
             case COMPLETE:
                 return true;
 
             case REJECT:
                 return false;
 
                 //accept
             default:
                 // determine if we need to visit our children 
                 Collection<String> subtreeIdsToVisit = context
                         .getSubtreeIdsToVisit(this);
                 boolean doVisitChildren = subtreeIdsToVisit != null
                         && !subtreeIdsToVisit.isEmpty();
                 if (doVisitChildren)
                 {
                     // visit the facets of the component
                     if (getFacetCount() > 0)
                     {
                         for (UIComponent facet : getFacets().values())
                         {
                             if (facet.visitTree(context, callback))
                             {
                                 return true;
                             }
                         }
                     }
                     Boolean skipIterationHint = (Boolean) context.getFacesContext().getAttributes().get(SKIP_ITERATION_HINT);
                     if (skipIterationHint != null && skipIterationHint.booleanValue())
                     {
                         // If SKIP_ITERATION is enabled, do not take into account rows.
                         for (int i = 0, childCount = getChildCount(); i < childCount; i++ )
                         {
                             UIComponent child = getChildren().get(i);
                             if (child.visitTree(context, callback))
                             {
                                 return true;
                             }
                         }
                     }
                     else
                     {
                         // visit every column directly without visiting its children 
                         // (the children of every UIColumn will be visited later for 
                         // every row) and also visit the column's facets
                         for (int i = 0, childCount = getChildCount(); i < childCount; i++)
                         {
                             UIComponent child = getChildren().get(i);
                             if (child instanceof UIColumn)
                             {
                                 VisitResult columnResult = context.invokeVisitCallback(child, callback);
                                 if (columnResult == VisitResult.COMPLETE)
                                 {
                                     return true;
                                 }
                                 if (child.getFacetCount() > 0)
                                 {
                                     for (UIComponent facet : child.getFacets().values())
                                     {
                                         if (facet.visitTree(context, callback))
                                         {
                                             return true;
                                         }
                                     }
                                 }
                             }
                         }
                         // iterate over the rows
                         int rowsToProcess = getRows();
                         // if getRows() returns 0, all rows have to be processed
                         if (rowsToProcess == 0)
                         {
                             rowsToProcess = getRowCount();
                         }
                         int rowIndex = getFirst();
                         for (int rowsProcessed = 0; rowsProcessed < rowsToProcess; rowsProcessed++, rowIndex++)
                         {
                             setRowIndex(rowIndex);
                             if (!isRowAvailable())
                             {
                                 return false;
                             }
                             // visit the children of every child of the UIData that is an instance of UIColumn
                             for (int i = 0, childCount = getChildCount(); i < childCount; i++)
                             {
                                 UIComponent child = getChildren().get(i);
                                 if (child instanceof UIColumn)
                                 {
                                     for (int j = 0, grandChildCount = child.getChildCount(); j < grandChildCount; j++)
                                     {
                                         UIComponent grandchild = child.getChildren().get(j);
                                         if (grandchild.visitTree(context, callback))
                                         {
                                             return true;
                                         }
                                     }
                                 }
                             }
                         }
                     }
                 }
             }
         }
         finally
         {
             // pop the component from EL and restore the old row index
             popComponentFromEL(context.getFacesContext());
             setRowIndex(oldRowIndex);
             if (!isCachedFacesContext)
             {
                 setCachedFacesContext(null);
             }
         }
 
         // Return false to allow the visiting to continue
         return false;
     }
 
     public void setVar(String var)
     {
         getStateHelper().put(PropertyKeys.var, var ); 
     }
 
     enum PropertyKeys
     {
          value
         , first
         , rows
         , var
         , uniqueIdCounter
     }
 
     @Override
     public String getFamily()
     {
         return COMPONENT_FAMILY;
     }
 }