/*
    * 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 org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFComponent;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFListener;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFWebConfigParam;
  
  import javax.el.ValueExpression;
  import javax.faces.application.FacesMessage;
  import javax.faces.application.ProjectStage;
  import javax.faces.context.ExternalContext;
  import javax.faces.context.FacesContext;
  import javax.faces.convert.Converter;
  import javax.faces.convert.ConverterException;
  import javax.faces.el.EvaluationException;
  import javax.faces.el.MethodBinding;
  import javax.faces.event.AbortProcessingException;
  import javax.faces.event.ExceptionQueuedEvent;
  import javax.faces.event.ExceptionQueuedEventContext;
  import javax.faces.event.FacesEvent;
  import javax.faces.event.PhaseId;
  import javax.faces.event.PostValidateEvent;
  import javax.faces.event.PreValidateEvent;
  import javax.faces.event.ValueChangeEvent;
  import javax.faces.event.ValueChangeListener;
  import javax.faces.render.Renderer;
  import javax.faces.validator.Validator;
  import javax.faces.webapp.FacesServlet;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  
  /**
   * UICommand is a base abstraction for components that implement ActionSource.
   * <p>
   * See the javadoc for this class in the <a href="http://java.sun.com/j2ee/javaserverfaces/1.2/docs/api/index.html">JSF
   * Specification</a> for further details.
   * <p>
   */
  @JSFComponent(defaultRendererType = "javax.faces.Text")
  public class UIInput extends UIOutput implements EditableValueHolder
  {
      public static final String COMPONENT_TYPE = "javax.faces.Input";
      public static final String COMPONENT_FAMILY = "javax.faces.Input";
  
      public static final String CONVERSION_MESSAGE_ID = "javax.faces.component.UIInput.CONVERSION";
      public static final String REQUIRED_MESSAGE_ID = "javax.faces.component.UIInput.REQUIRED";
      public static final String UPDATE_MESSAGE_ID = "javax.faces.component.UIInput.UPDATE";
  
      /**
       * Force validation on empty fields (By default is auto, which means it is only 
       * enabled when Bean Validation binaries are available on the current classpath).
       */
      @JSFWebConfigParam(defaultValue="auto", expectedValues="auto, true, false", since="2.0", group="validation")
      public static final String VALIDATE_EMPTY_FIELDS_PARAM_NAME = "javax.faces.VALIDATE_EMPTY_FIELDS";
      
      /** 
       * Submitted values are decoded as null values instead empty strings.
       * 
       * <p>Note this param is ignored for components extending from UISelectOne/UISelectMany.</p>
       **/
      @JSFWebConfigParam(defaultValue="false", expectedValues="true, false", since="2.0", group="validation")
      private static final String EMPTY_VALUES_AS_NULL_PARAM_NAME
              = "javax.faces.INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL";
  
      // our own, cached key
      private static final String MYFACES_EMPTY_VALUES_AS_NULL_PARAM_NAME =
        "org.apache.myfaces.UIInput.INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL";
      
      /**
       * Extended debug info is stored under this key in the request
       * map for every UIInput component when in Development mode.
       * ATTENTION: this constant is duplicate in org.apache.myfaces.renderkit.ErrorPageWriter
       */
      private static final String DEBUG_INFO_KEY = "org.apache.myfaces.debug.DEBUG_INFO";
  
      private static final Validator[] EMPTY_VALIDATOR_ARRAY = new Validator[0];
     
     private _DeltaList<Validator> _validatorList;
 
     /**
      * Construct an instance of the UIInput.
      */
     public UIInput()
     {
         setRendererType("javax.faces.Text");
     }
 
     @Override
     public String getFamily()
     {
         return COMPONENT_FAMILY;
     }
 
     /**
      * Store the specified object as the "local value" of this component. The value-binding named "value" (if any) is
      * ignored; the object is only stored locally on this component. During the "update model" phase, if there is a
      * value-binding named "value" then this local value will be stored via that value-binding and the "local value"
      * reset to null.
      */
     @Override
     public void setValue(Object value)
     {
         FacesContext facesContext = getFacesContext();
         if (facesContext != null && facesContext.isProjectStage(ProjectStage.Development))
         {
             // extended debug-info when in Development mode
             _createFieldDebugInfo(facesContext, "localValue",
                     getLocalValue(), value, 1);
         }
         setLocalValueSet(true);
         super.setValue(value);
     }
     
     /**
      * Return the current value of this component.
      * <p>
      * If a submitted value has been converted but not yet pushed into the
      * model, then return that locally-cached value (see isLocalValueSet).
      * <p>
      * Otherwise, evaluate an EL expression to fetch a value from the model. 
      */
     public Object getValue()
     {
         if (isLocalValueSet())
         {
             return super.getLocalValue();
         }
         return super.getValue();
     }
 
     /**
      * Set the "submitted value" of this component from the relevant data in the current servlet request object.
      * <p>
      * If this component is not rendered, then do nothing; no output would have been sent to the client so no input is
      * expected.
      * <p>
      * Invoke the inherited functionality, which typically invokes the renderer associated with this component to
      * extract and set this component's "submitted value".
      * <p>
      * If this component is marked "immediate", then immediately apply validation to the submitted value found. On
      * error, call context method "renderResponse" which will force processing to leap to the "render
      * response" phase as soon as the "decode" step has completed for all other components.
      */
     @Override
     public void processDecodes(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
         super.processDecodes(context);
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (isImmediate())
             {
                 //Pre validation event dispatch for component
                 context.getApplication().publishEvent(context,  PreValidateEvent.class, getClass(), this);
                 try
                 {
                     validate(context);
                 }
                 catch (RuntimeException e)
                 {
                     context.renderResponse();
                     throw e;
                 }
                 finally
                 {
                     context.getApplication().publishEvent(context,  PostValidateEvent.class, getClass(), this);
                 }
                 if (!isValid())
                 {
                     context.renderResponse();
                 }
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
     }
 
     @Override
     public void processValidators(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
 
         //super.processValidators(context);
         
         // Call the processValidators() method of all facets and children of this UIComponent, in the order
         // determined by a call to getFacetsAndChildren().
         int facetCount = getFacetCount();
         if (facetCount > 0)
         {
             for (UIComponent facet : getFacets().values())
             {
                 facet.processValidators(context);
             }
         }
 
         for (int i = 0, childCount = getChildCount(); i < childCount; i++)
         {
             UIComponent child = getChildren().get(i);
             child.processValidators(context);
         }
 
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isImmediate())
             {
                 //Pre validation event dispatch for component
                 context.getApplication().publishEvent(context,  PreValidateEvent.class, getClass(), this);
                 try
                 {
                     validate(context);
                 }
                 catch (RuntimeException e)
                 {
                     context.renderResponse();
                     throw e;
                 }
                 finally
                 {
                     context.getApplication().publishEvent(context,  PostValidateEvent.class, getClass(), this);
                 }
                 if (!isValid())
                 {
                     context.validationFailed();
                     context.renderResponse();
                 }
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
     }
 
     @Override
     public void processUpdates(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             if (!isRendered())
             {
                 return;
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
         super.processUpdates(context);
 
         try
         {
             setCachedFacesContext(context);
             pushComponentToEL(context, this);
             try
             {
                 updateModel(context);
             }
             catch (RuntimeException e)
             {
                 context.renderResponse();
                 throw e;
             }
             if (!isValid())
             {
                 context.renderResponse();
             }
         }
         finally
         {
             setCachedFacesContext(null);
             popComponentFromEL(context);
         }
     }
 
     @Override
     public void decode(FacesContext context)
     {
         // We (re)set to valid, so that component automatically gets (re)validated
         setValid(true);
         super.decode(context);
     }
 
     @Override
     public void broadcast(FacesEvent event) throws AbortProcessingException
     {
         // invoke standard listeners attached to this component first
         super.broadcast(event);
 
         // Check if the event is applicable for ValueChangeListener
         if (event instanceof ValueChangeEvent)
         {
             // invoke the single listener defined directly on the component
             MethodBinding valueChangeListenerBinding = getValueChangeListener();
             if (valueChangeListenerBinding != null)
             {
                 try
                 {
                     valueChangeListenerBinding.invoke(getFacesContext(), new Object[] { event });
                 }
                 catch (EvaluationException e)
                 {
                     Throwable cause = e.getCause();
                     if (cause != null && cause instanceof AbortProcessingException)
                     {
                         throw (AbortProcessingException) cause;
                     }
                     else
                     {
                         throw e;
                     }
                 }
             }
         }
     }
 
     public void updateModel(FacesContext context)
     {
         if (!isValid())
         {
             return;
         }
         if (!isLocalValueSet())
         {
             return;
         }
         ValueExpression expression = getValueExpression("value");
         if (expression == null)
         {
             return;
         }
 
         try
         {
             expression.setValue(context.getELContext(), getLocalValue());
             setValue(null);
             setLocalValueSet(false);
         }
         catch (Exception e)
         {
             // Enqueue an error message
             //context.getExternalContext().log(e.getMessage(), e);
             
             // Create a FacesMessage with the id UPDATE_MESSAGE_ID
             FacesMessage facesMessage = _MessageUtils.getMessage(context,
                     context.getViewRoot().getLocale(), FacesMessage.SEVERITY_ERROR, UPDATE_MESSAGE_ID,
                     new Object[] { _MessageUtils.getLabel(context, this) });
             
             // create an UpdateModelException and enqueue it since 
             // we are not allowed to throw it directly here
             // spec javadoc: The exception must not be re-thrown. This enables tree traversal to 
             // continue for this lifecycle phase, as in all the other lifecycle phases.
             UpdateModelException updateModelException = new UpdateModelException(facesMessage, e);
             ExceptionQueuedEventContext exceptionQueuedContext 
                     = new ExceptionQueuedEventContext(context, updateModelException, this, PhaseId.UPDATE_MODEL_VALUES);
             
             // spec javadoc says we should call context.getExceptionHandler().processEvent(exceptionQueuedContext),
             // which is not just syntactically wrong, but also stupid!!
             context.getApplication().publishEvent(context, ExceptionQueuedEvent.class, exceptionQueuedContext);
             
             // Set the valid property of this UIInput to false
             setValid(false);
         }
     }
 
     protected void validateValue(FacesContext context, Object convertedValue)
     {
         if (!isValid())
         {
             return;
         }
 
         // If our value is empty, check the required property
         boolean isEmpty = isEmpty(convertedValue); 
 
         if (isRequired() && isEmpty)
         {
             if (getRequiredMessage() != null)
             {
                 String requiredMessage = getRequiredMessage();
                 context.addMessage(this.getClientId(context), new FacesMessage(FacesMessage.SEVERITY_ERROR,
                     requiredMessage, requiredMessage));
             }
             else
             {
                 _MessageUtils.addErrorMessage(context, this, REQUIRED_MESSAGE_ID,
                     new Object[] { _MessageUtils.getLabel(context, this) });
             }
             setValid(false);
             return;
         }
 
         if (!isEmpty || shouldValidateEmptyFields(context))
         {
             _ComponentUtils.callValidators(context, this, convertedValue);
         }
     }
     
     /**
      * Checks if the <code>validate()</code> should interpret an empty
      * submitted value should be handle as <code>NULL</code>
      * 
      * @return a (cached) boolean to identify the interpretation as null
      */
     private boolean shouldInterpretEmptyStringSubmittedValuesAsNull(FacesContext context)
     {
         ExternalContext ec = context.getExternalContext();
         Boolean interpretEmptyStringAsNull
                 = (Boolean)ec.getApplicationMap().get(MYFACES_EMPTY_VALUES_AS_NULL_PARAM_NAME);
 
         // not yet cached...
         if (interpretEmptyStringAsNull == null)
         {
             // parses the web.xml to get the "javax.faces.INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL" value
             String param = ec.getInitParameter(EMPTY_VALUES_AS_NULL_PARAM_NAME);
 
             // evaluate the param
             interpretEmptyStringAsNull = "true".equalsIgnoreCase(param);
 
             // cache the parsed value
             ec.getApplicationMap().put(MYFACES_EMPTY_VALUES_AS_NULL_PARAM_NAME, interpretEmptyStringAsNull);
         }
 
         return interpretEmptyStringAsNull;
     }
 
     /**
      * <p>Return <code>true</code> if the value is an empty <code>String</code>.</p>
      */
     private boolean isEmptyString(Object value)
     {
         return ((value instanceof String) && (((String) value).length() == 0));
     }
 
     private boolean shouldValidateEmptyFields(FacesContext context)
     {
         ExternalContext extCtx = context.getExternalContext();
         String validateEmptyFields = (String) extCtx.getInitParameter(VALIDATE_EMPTY_FIELDS_PARAM_NAME);
         if (validateEmptyFields == null)
         {
             validateEmptyFields = (String) extCtx.getApplicationMap().get(VALIDATE_EMPTY_FIELDS_PARAM_NAME);
         }
 
         // null means the same as auto.
         if (validateEmptyFields == null)
         {
             validateEmptyFields = "auto";
         }
         else
         {
             // The environment variables are case insensitive.
             validateEmptyFields = validateEmptyFields.toLowerCase();
         }
 
         if (validateEmptyFields.equals("auto") && _ExternalSpecifications.isBeanValidationAvailable())
         {
             return true;
         }
         else if (validateEmptyFields.equals("true"))
         {
             return true;
         }
         return false;
     }
 
     /**
      * Determine whether the new value is valid, and queue a ValueChangeEvent if necessary.
      * <p>
      * The "submitted value" is converted to the necessary type; conversion failure is reported as an error and
      * validation processing terminates for this component. See documentation for method getConvertedValue for details
      * on the conversion process.
      * <p>
      * Any validators attached to this component are then run, passing the converted value.
      * <p>
      * The old value of this component is then fetched (possibly involving the evaluation of a value-binding expression,
      * ie invoking a method on a user object). The old value is compared to the new validated value, and if they are
      * different then a ValueChangeEvent is queued for later processing.
      * <p>
      * On successful completion of this method:
      * <ul>
      * <li>isValid() is true
      * <li>isLocalValueSet() is true
      * <li>submittedValue is reset to null
      * <li>a ValueChangeEvent is queued if the new value != old value
      * </ul>
      */
     public void validate(FacesContext context)
     {
         if (context == null)
         {
             throw new NullPointerException("context");
         }
 
         Object submittedValue = getSubmittedValue();
         if (submittedValue == null)
         {
             return;
         }
 
         // Begin new JSF 2.0 requirement (INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL)
         if (shouldInterpretEmptyStringSubmittedValuesAsNull(context) && isEmptyString(submittedValue))
         {   
             // -= matzew = setSubmittedValue(null) is wrong, see:
             // https://javaserverfaces-spec-public.dev.java.net/issues/show_bug.cgi?id=671
             setSubmittedValue(null);
             submittedValue = null;
         }
         // End new JSF 2.0 requirement (INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL)
 
         Object convertedValue;
         try
         {
             convertedValue = getConvertedValue(context, submittedValue);
         }
         catch (ConverterException e)
         {
             String converterMessage = getConverterMessage();
             if (converterMessage != null)
             {
                 context.addMessage(getClientId(context), new FacesMessage(FacesMessage.SEVERITY_ERROR,
                         converterMessage, converterMessage));
             }
             else
             {
                 FacesMessage facesMessage = e.getFacesMessage();
                 if (facesMessage != null)
                 {
                     context.addMessage(getClientId(context), facesMessage);
                 }
                 else
                 {
                     _MessageUtils.addErrorMessage(context, this, CONVERSION_MESSAGE_ID,
                             new Object[] { _MessageUtils.getLabel(context, this) });
                 }
             }
             setValid(false);
             return;
         }
 
         validateValue(context, convertedValue);
 
         if (!isValid())
         {
             return;
         }
 
         Object previousValue = getValue();
         setValue(convertedValue);
         setSubmittedValue(null);
         if (compareValues(previousValue, convertedValue))
         {
             queueEvent(new ValueChangeEvent(this, previousValue, convertedValue));
         }
     }
 
     /**
      * Convert the provided object to the desired value.
      * <p>
      * If there is a renderer for this component, then call the renderer's getConvertedValue method. While this can of
      * course be implemented in any way the renderer desires, it typically performs exactly the same processing that
      * this method would have done anyway (ie that described below for the no-renderer case).
      * <p>
      * Otherwise:
      * <ul>
      * <li>If the submittedValue is not a String then just return the submittedValue unconverted.
      * <li>If there is no "value" value-binding then just return the submittedValue unconverted.
      * <li>Use introspection to determine the type of the target property specified by the value-binding, and then use
      * Application.createConverter to find a converter that can map from String to the required type. Apply the
      * converter to the submittedValue and return the result.
      * </ul>
      */
     protected Object getConvertedValue(FacesContext context, Object submittedValue) throws ConverterException
     {
         Renderer renderer = getRenderer(context);
         if (renderer != null)
         {
             return renderer.getConvertedValue(context, this, submittedValue);
         }
         else if (submittedValue instanceof String)
         {
             Converter converter = _SharedRendererUtils.findUIOutputConverter(context, this);
             if (converter != null)
             {
                 return converter.getAsObject(context, this, (String) submittedValue);
             }
         }
         return submittedValue;
     }
 
     protected boolean compareValues(Object previous, Object value)
     {
         return previous == null ? (value != null) : (!previous.equals(value));
     }
 
     /**
      * @since 1.2
      */
     public void resetValue()
     {
         setSubmittedValue(null);
         setValue(null);
         setLocalValueSet(false);
         setValid(true);
     }
     
     /**
      * A boolean value that identifies the phase during which action events should fire.
      * <p>
      * During normal event processing, action methods and action listener methods are fired during the
      * "invoke application" phase of request processing. If this attribute is set to "true", these methods are fired
      * instead at the end of the "apply request values" phase.
      * </p>
      */
     @JSFProperty
     public boolean isImmediate()
     {
         return (Boolean) getStateHelper().eval(PropertyKeys.immediate, Boolean.FALSE);
     }
 
     public void setImmediate(boolean immediate)
     {
         getStateHelper().put(PropertyKeys.immediate, immediate );
     }
 
     /**
      * A boolean value that indicates whether an input value is required.
      * <p>
      * If this value is true and no input value is provided by a postback operation, then the "requiredMessage" text is
      * registered as a FacesMessage for the request, and validation fails.
      * </p>
      * <p>
      * Default value: false.
      * </p>
      */
     @JSFProperty(defaultValue = "false")
     public boolean isRequired()
     {
         return (Boolean) getStateHelper().eval(PropertyKeys.required, Boolean.FALSE);
     }
 
     public void setRequired(boolean required)
     {
         getStateHelper().put(PropertyKeys.required, required ); 
     }
 
     /**
      * Text to be displayed to the user as an error message when conversion of a submitted value to the target type
      * fails.
      * <p>
      * </p>
      */
     @JSFProperty
     public String getConverterMessage()
     {
         return (String) getStateHelper().eval(PropertyKeys.converterMessage);
     }
 
     public void setConverterMessage(String converterMessage)
     {
         getStateHelper().put(PropertyKeys.converterMessage, converterMessage );
     }
 
     /**
      * Text to be displayed to the user as an error message when this component is marked as "required" but no input
      * data is present during a postback (ie the user left the required field blank).
      */
     @JSFProperty
     public String getRequiredMessage()
     {
         return (String) getStateHelper().eval(PropertyKeys.requiredMessage);
     }
 
     public void setRequiredMessage(String requiredMessage)
     {
         getStateHelper().put(PropertyKeys.requiredMessage, requiredMessage );
     }
 
     /**
      * A method-binding EL expression which is invoked during the validation phase for this component.
      * <p>
      * The invoked method is expected to check the submitted value for this component, and if not acceptable then report
      * a validation error for the component.
      * </p>
      * <p>
      * The method is expected to have the prototype
      * </p>
      * <code>public void aMethod(FacesContext, UIComponent,Object)</code>
      * 
      * @deprecated
      */
     @SuppressWarnings("dep-ann")
     @JSFProperty(stateHolder=true, returnSignature = "void",
             methodSignature = "javax.faces.context.FacesContext,javax.faces.component.UIComponent,java.lang.Object")
     public MethodBinding getValidator()
     {
         return (MethodBinding) getStateHelper().eval(PropertyKeys.validator);
     }
 
     /** See getValidator.
      *  
      * @deprecated 
      */
     public void setValidator(MethodBinding validator)
     {
         getStateHelper().put(PropertyKeys.validator, validator);
     }
 
     /** See getValidator. */
     public void addValidator(Validator validator)
     {
         if (validator == null)
         {
             throw new NullPointerException("validator");
         }
         
         if (_validatorList == null)
         {
             //normally add user 0-3 validators: 
             _validatorList = new _DeltaList<Validator>(new ArrayList<Validator>(3));
         }
 
         _validatorList.add(validator);
         
         // The argument validator must be inspected for the presence of the ResourceDependency annotation.
         //_handleAnnotations(FacesContext.getCurrentInstance(), validator);
     }
 
     /** See getValidator. */
     public void removeValidator(Validator validator)
     {
         if (validator == null || _validatorList == null)
         {
             return;
         }
 
         _validatorList.remove(validator);
     }
 
     /** See getValidator. */
     public Validator[] getValidators()
     {
         return _validatorList == null ? EMPTY_VALIDATOR_ARRAY
                 : _validatorList.toArray(new Validator[_validatorList.size()]);
     }
 
     /**
      * Text which will be shown if validation fails.
      */
     @JSFProperty
     public String getValidatorMessage()
     {
         return (String) getStateHelper().eval(PropertyKeys.validatorMessage);
     }
 
     public void setValidatorMessage(String validatorMessage)
     {
         getStateHelper().put(PropertyKeys.validatorMessage, validatorMessage );
     }
 
     /**
      * A method which is invoked during postback processing for the current view if the submitted value for this
      * component is not equal to the value which the "value" expression for this component returns.
      * <p>
      * The phase in which this method is invoked can be controlled via the immediate attribute.
      * </p>
      * 
      * @deprecated
      */
     @JSFProperty(stateHolder=true, returnSignature = "void",
                  methodSignature = "javax.faces.event.ValueChangeEvent", clientEvent="valueChange")
     public MethodBinding getValueChangeListener()
     {
         return (MethodBinding) getStateHelper().eval(PropertyKeys.valueChangeListener);
     }
 
     /**
      * See getValueChangeListener.
      * 
      * @deprecated
      */
     public void setValueChangeListener(MethodBinding valueChangeListener)
     {
         getStateHelper().put(PropertyKeys.valueChangeListener, valueChangeListener);
     }
 
     /**
      * Specifies whether the component's value is currently valid, ie whether the validators attached to this component
      * have allowed it.
      */
     @JSFProperty(defaultValue = "true", tagExcluded = true)
     public boolean isValid()
     {
         Object value = getStateHelper().get(PropertyKeys.valid);
         if (value != null)
         {
             return (Boolean) value;        
         }
         return true; 
     }
 
     public void setValid(boolean valid)
     {
         // default value for valid is true, so if the intention is to save the default
         // value when nothing else was set before, don't do it. This is done in order to
         // reduce the size of the saved state of the state helper. Default values won't be
         // included in the saved state. 
         if (getStateHelper().get(PropertyKeys.valid) != null || !valid)
         {
             getStateHelper().put(PropertyKeys.valid, valid );
         }
     }
 
     /**
      * Specifies whether a local value is currently set.
      * <p>
      * If false, values are being retrieved from any attached ValueBinding.
      */
     @JSFProperty(defaultValue = "false", tagExcluded = true)
     public boolean isLocalValueSet()
     {
         Object value = getStateHelper().get(PropertyKeys.localValueSet);
         if (value != null)
         {
             return (Boolean) value;        
         }
         return false;
     }
 
     public void setLocalValueSet(boolean localValueSet)
     {
         // default value for localValueSet is false, so if the intention is to save the default
         // value when nothing else was set before, don't do it. This is done in order to
         // reduce the size of the saved state of the state helper. Default values won't be
         // included in the saved state.
         if (getStateHelper().get(PropertyKeys.localValueSet) != null || localValueSet)
         {
             getStateHelper().put(PropertyKeys.localValueSet, localValueSet );
         }
     }
 
     /**
      * Gets the current submitted value. This value, if non-null, is set by the Renderer to store a possibly invalid
      * value for later conversion or redisplay, and has not yet been converted into the proper type for this component
      * instance. This method should only be used by the decode() and validate() method of this component, or its
      * corresponding Renderer; however, user code may manually set it to null to erase any submitted value.
      */
     @JSFProperty(tagExcluded = true)
     public Object getSubmittedValue()
     {
         return  getStateHelper().get(PropertyKeys.submittedValue);
     }
 
     public void setSubmittedValue(Object submittedValue)
     {
         FacesContext facesContext = getFacesContext();
         if (facesContext != null && facesContext.isProjectStage(ProjectStage.Development))
         {
             // extended debug-info when in Development mode
             _createFieldDebugInfo(facesContext, "submittedValue",
                     getSubmittedValue(), submittedValue, 1);
         }
         getStateHelper().put(PropertyKeys.submittedValue, submittedValue );
     }
 
     public void addValueChangeListener(ValueChangeListener listener)
     {
         addFacesListener(listener);
     }
 
     public void removeValueChangeListener(ValueChangeListener listener)
     {
         removeFacesListener(listener);
     }
 
     /**
      * The valueChange event is delivered when the value attribute
      * is changed.
      */
     @JSFListener(event="javax.faces.event.ValueChangeEvent")
     public ValueChangeListener[] getValueChangeListeners()
     {
         return (ValueChangeListener[]) getFacesListeners(ValueChangeListener.class);
     }
 
     enum PropertyKeys
     {
          immediate
         , required
         , converterMessage
         , requiredMessage
         , validator
         , validatorListSet
         , validatorMessage
         , valueChangeListener
         , valid
         , localValueSet
         , submittedValue
     }
     
     public void markInitialState()
     {
         super.markInitialState();
         if (_validatorList != null)
         {
             _validatorList.markInitialState();
         }
     }
     
     public void clearInitialState()
     {
         if (initialStateMarked())
         {
             super.clearInitialState();
             if (_validatorList != null)
             {
                 _validatorList.clearInitialState();
             }
         }
     }    
 
     @Override
     public Object saveState(FacesContext facesContext)
     {
         if (initialStateMarked())
         {
             Object parentSaved = super.saveState(facesContext);
             Object validatorListSaved = saveValidatorList(facesContext);
             if (parentSaved == null && validatorListSaved == null)
             {
                 //No values
                 return null;
             }
             
             Object[] values = new Object[2];
             values[0] = parentSaved;
             values[1] = validatorListSaved;
             return values;
         }
         else
         {
             Object[] values = new Object[2];
             values[0] = super.saveState(facesContext);
             values[1] = saveValidatorList(facesContext);
             return values;
         }
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public void restoreState(FacesContext facesContext, Object state)
     {
         if (state == null)
         {
             return;
         }
         
         Object[] values = (Object[])state;
         super.restoreState(facesContext,values[0]);
         if (values[1] instanceof _AttachedDeltaWrapper)
         {
             //Delta
             if (_validatorList != null)
             {
                 ((StateHolder)_validatorList).restoreState(facesContext,
                         ((_AttachedDeltaWrapper) values[1]).getWrappedStateObject());
             }
         }
         else if (values[1] != null || !initialStateMarked())
         {
             //Full
             _validatorList = (_DeltaList<Validator>)
                 restoreAttachedState(facesContext,values[1]);
         }
     }
     
     private Object saveValidatorList(FacesContext facesContext)
     {
         PartialStateHolder holder = (PartialStateHolder) _validatorList;
         if (initialStateMarked() && _validatorList != null && holder.initialStateMarked())
         {                
             Object attachedState = holder.saveState(facesContext);
             if (attachedState != null)
             {
                 return new _AttachedDeltaWrapper(_validatorList.getClass(),
                         attachedState);
             }
             //_validatorList instances once is created never changes, we can return null
             return null;
         }
         else
         {
             return saveAttachedState(facesContext,_validatorList);
         }            
     }
     
     /**
      * Returns the debug-info Map for this component.
      * @return
      */
     @SuppressWarnings("unchecked")
     private Map<String, List<Object[]>> _getDebugInfoMap()
     {
         Map<String, Object> requestMap = getFacesContext()
                 .getExternalContext().getRequestMap();
         Map<String, List<Object[]>> debugInfo = (Map<String, List<Object[]>>) 
                 requestMap.get(DEBUG_INFO_KEY + getClientId());
         if (debugInfo == null)
         {
             // no debug info available yet, create one and put it on the attributes map
             debugInfo = new HashMap<String, List<Object[]>>();
             requestMap.put(DEBUG_INFO_KEY + getClientId(), debugInfo);
         }
         return debugInfo;
     }
     
     /**
      * Returns the field's debug-infos from the component's debug-info Map.
      * @param field
      * @return
      */
     private List<Object[]> _getFieldDebugInfos(final String field)
     {
         Map<String, List<Object[]>> debugInfo = _getDebugInfoMap();
         List<Object[]> fieldDebugInfo = debugInfo.get(field);
         if (fieldDebugInfo == null)
         {
             // no field debug-infos yet, create them and store it in the Map
             fieldDebugInfo = new ArrayList<Object[]>();
             debugInfo.put(field, fieldDebugInfo);
         }
         return fieldDebugInfo;
     }
     
     /**
      * Creates the field debug-info for the given field, which changed
      * from oldValue to newValue.
      * 
      * @param facesContext
      * @param field
      * @param oldValue
      * @param newValue
      * @param skipStackTaceElements How many StackTraceElements should be skipped
      *                              when the calling function will be determined.
      */
     private void _createFieldDebugInfo(FacesContext facesContext,
             final String field, Object oldValue, 
             Object newValue, final int skipStackTaceElements)
     {
         if (oldValue == null && newValue == null)
         {
             // both values are null, not interesting and can
             // happen a lot in UIData with saving and restoring state
             return;
         }
         
         if (facesContext.getViewRoot() == null)
         {
             // No viewRoot set, it is creating component, 
             // so it is not possible to calculate the clientId, 
             // abort processing because the interesting part will
             // happen later.
             return;
         }
         
         if (getParent() == null || !isInView())
         {
             //Skip if no parent or is not in view
             return;
         }
         
         // convert Array values into a more readable format
         if (oldValue != null && oldValue.getClass().isArray() && Object[].class.isAssignableFrom(oldValue.getClass()))
         {
             oldValue = Arrays.deepToString((Object[]) oldValue);
         }
         if (newValue != null && newValue.getClass().isArray() && Object[].class.isAssignableFrom(newValue.getClass()))
         {
             newValue = Arrays.deepToString((Object[]) newValue);
         }
         
         // use Throwable to get the current call stack
         Throwable throwableHelper = new Throwable();
         StackTraceElement[] stackTraceElements = throwableHelper.getStackTrace();
         List<StackTraceElement> debugStackTraceElements = new LinkedList<StackTraceElement>();
         
         // + 1 because this method should also be skipped
         for (int i = skipStackTaceElements + 1; i < stackTraceElements.length; i++)
         {
             debugStackTraceElements.add(stackTraceElements[i]);
             
             if (FacesServlet.class.getCanonicalName()
                     .equals(stackTraceElements[i].getClassName()))
             {
                 // stop after the FacesServlet
                 break;
             }
         }
         
         // create the debug-info array
         // structure:
         //     - 0: phase
         //     - 1: old value
         //     - 2: new value
         //     - 3: StackTraceElement List
         // NOTE that we cannot create a class here to encapsulate this data,
         // because this is not on the spec and the class would not be available in impl.
         Object[] debugInfo = new Object[4];
         debugInfo[0] = facesContext.getCurrentPhaseId();
         debugInfo[1] = oldValue;
         debugInfo[2] = newValue;
         debugInfo[3] = debugStackTraceElements;
         
         // add the debug info
         _getFieldDebugInfos(field).add(debugInfo);
     }
     
     /**
      * Check if a value is empty or not. Since we don't know the class of
      * value we have to check and deal with it properly.
      * 
      * @since 2.0
      * @param value
      * @return
      */
     public static boolean isEmpty(Object value)
     {
         if (value == null)
         {
             return true;
         }
         else if (value instanceof String)
         {
             if ( ((String)value).trim().length() <= 0 )
             {
                 return true;
             }
         }
         else if (value instanceof Collection)
         {
             if ( ((Collection)value).isEmpty())
             {
                 return true;
             }
         }
         else if (value.getClass().isArray())
         {
             if (java.lang.reflect.Array.getLength(value) <= 0)
             {
                 return true;
             }
         }
         else if (value instanceof Map)
         {
             if ( ((Map)value).isEmpty())
             {
                 return true;
             }
         }
         return false;
     }
 
 }