2009/05/20 - Apache Shale has been retired.

 /*

  * 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 org.apache.shale.validator.faces;

 import java.io.IOException;

 import java.io.StringWriter;

 import javax.faces.component.UICommand;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 import javax.faces.context.ResponseWriter;

 import javax.faces.convert.ConverterException;

 import javax.faces.render.Renderer;

 /**

  * <p>This Renderer is a hybrid renderer decorator that is dynamically

  * registered by {@link ValidatorRenderKit}

  * for component renderers in the "javax.faces.Command" family.</p>

  */

 public class ValidatorCommandRenderer extends Renderer {

     /**

      * <p>The Original Renderer.</p>

      */

     private Renderer defaultRenderer = null;

     /**

      * <p>The overloaded constructor is passed the original

      * <code>Renderer</code> for the family and component type.</p>

      *

      * @param defaultRenderer The default Renderer we should delegate to

      */

     public ValidatorCommandRenderer(Renderer defaultRenderer) {

        this.defaultRenderer = defaultRenderer;

     }

     /**

      * <p>Attribute name used to override the default behavior of how the immediate

      * attribute effects the execution of client side javascript validation.</p>

      */

     public static final String OVERRIDE_IMMEDIATE = "org.apache.shale.validator.immediate";

     private static final int ENCODE_BEGIN = 0;

     private static final int ENCODE_CHILDREN = 1;

     private static final int ENCODE_END = 2;

     /**

      * <b>Interrogates the component's immediate property and the component's

      * immediate override attribute to determine if client side validation is

      * invoked. If either the property or attribute override is false, client

      * side validation is invoked. Otherwise, the response writer is hijacked

      * and the original render is invoked. The result is buffered and a

      * statement of javascript is injected into the onclick event which cancels

      * client side validation. The original response writer is restored and the

      * modified markup is written to the response writer. The

      * <code>encodeSwitch</code> determines if the encodeBegin, encodeChildren

      * or encodeEnd methods should be invoked on the decorated renderer.</b>

      *

      * @param context FacesContext for the current request

      * @param component UIComponent being rendered

      * @param encodeSwitch FIXME - encode switch?

      *

      * @exception IOException if an input/output error occurs

      */

     protected void encode(FacesContext context, UIComponent component,

             int encodeSwitch) throws IOException {

         UICommand command = (UICommand) component;

         // look for a override to the default

         boolean immediateOverride = true;

         String attr = (String) component.getAttributes()

                 .get(OVERRIDE_IMMEDIATE);

         if (attr != null) {

             immediateOverride = Boolean.valueOf(attr).booleanValue();

         }

         if (command.isImmediate() && immediateOverride) {

             ResponseWriter hijackedWriter = context.getResponseWriter();

             // builds a buffer to write the page to

             StringWriter writer = new StringWriter();

             // create a buffered response writer

             ResponseWriter buffResponsewriter = context.getRenderKit()

                     .createResponseWriter(writer, null,

                             hijackedWriter.getCharacterEncoding());

             // push buffered writer to the faces context

             context.setResponseWriter(buffResponsewriter);

             if (encodeSwitch == ENCODE_BEGIN) {

                 defaultRenderer.encodeBegin(context, component);

             } else if (encodeSwitch == ENCODE_CHILDREN) {

                 defaultRenderer.encodeChildren(context, component);

             } else {

                 defaultRenderer.encodeEnd(context, component);

             }

             buffResponsewriter.write(' ');

             buffResponsewriter.flush();

             buffResponsewriter.close();

             writer.flush();

             writer.close();

             StringBuffer buff = writer.getBuffer();

             int i = buff.indexOf("onclick=\"");

             if (i > 0) {

                 buff.insert(i + "onclick=\"".length(), "bCancel=true;");

             }

             hijackedWriter.write(buff.toString());

             context.setResponseWriter(hijackedWriter);

         } else {

             if (encodeSwitch == ENCODE_BEGIN) {

                 defaultRenderer.encodeBegin(context, component);

             } else if (encodeSwitch == ENCODE_CHILDREN) {

                 defaultRenderer.encodeChildren(context, component);

             } else {

                 defaultRenderer.encodeEnd(context, component);

             }

         }

     }

     /** {@inheritDoc} */

     public String convertClientId(FacesContext context, String id) {

         return defaultRenderer.convertClientId(context, id);

     }

     /** {@inheritDoc} */

     public Object getConvertedValue(FacesContext context, UIComponent component, Object o) throws ConverterException {

         return defaultRenderer.getConvertedValue(context, component, o);

     }

     /** {@inheritDoc} */

     public void decode(FacesContext context, UIComponent component) {

         defaultRenderer.decode(context, component);

     }

     /**

      * <p>

      * Invokes the <code>encode</code> method passing

      * <code>ENCODE_BEGIN</code> for the encodeSwitch parameter.

      * </p>

      *

      * @param context FacesContext for the current request

      * @param component UIComponent being rendered

      *

      * @exception IOException if an input/output error occurs

      */

     public void encodeBegin(FacesContext context, UIComponent component)

             throws IOException {

         encode(context, component, ENCODE_BEGIN);

     }

     /**

      * <p>Invokes the <code>encode</code> method passing

      * <code>ENCODE_CHILDREN</code> for the encodeSwitch parameter.</p>

      *

      * @param context FacesContext for the current request

      * @param component UIComponent being rendered

      *

      * @exception IOException if an input/output error occurs

      */

     public void encodeChildren(FacesContext context, UIComponent component)

             throws IOException {

         encode(context, component, ENCODE_CHILDREN);

     }

     /**

      * <p>Invokes the <code>encode</code> method passing <code>ENCODE_END</code>

      * for the encodeSwitch parameter.</p>

      *

      * @param context FacesContext for the current reqauest

      * @param component UIComponent being rendered

      *

      * @exception IOException if an input/output error occurs

      */

     public void encodeEnd(FacesContext context, UIComponent component)

             throws IOException {

         encode(context, component, ENCODE_END);

     }

     /** {@inheritDoc} */

     public boolean getRendersChildren() {

         return defaultRenderer.getRendersChildren();

     }

 }