trinidad-impl/src/main/java/org/apache/myfaces/trinidadinternal/renderkit/core/CoreResponseStateManager.java - myfaces-trinidad - Git at Google

 /*
  * 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.myfaces.trinidadinternal.renderkit.core;

 import java.io.IOException;

 import java.util.Map;

 import javax.faces.FacesException;
 import javax.faces.application.StateManager;
 import javax.faces.context.ExternalContext;
 import javax.faces.context.FacesContext;
 import javax.faces.context.ResponseWriter;
 import javax.faces.render.ResponseStateManager;

 import org.apache.myfaces.trinidad.logging.TrinidadLogger;
 import org.apache.myfaces.trinidadinternal.application.StateManagerImpl;
 import org.apache.myfaces.trinidadinternal.util.JsfUtils;
 import org.apache.myfaces.trinidadinternal.util.StateUtils;

 /**
  * ResponseStateManager implementation for the Core RenderKit.
  * <p>
  */
 public class CoreResponseStateManager extends ResponseStateManager
 {

   @Override
   public Object getState(FacesContext context, String viewId)
   {
     // TODO see doc in StateManagerImpl.restoreView
     // (search for StateManagerImpl.RESPONSE_STATE_MANAGER_STATE_KEY) to see doc
     // about what's going on here
     Object state = context.getExternalContext().getRequestMap().get(
                                               StateManagerImpl.RESPONSE_STATE_MANAGER_STATE_KEY);

     if (state != null)
       return state;
     else
       return super.getState(context, viewId);
   }


   /**
    * Name of the form field that encodes the UI state.
    */
   static public final String FORM_FIELD_NAME = "org.apache.myfaces.trinidad.faces.FORM";

   /**
    * Write the state into the page.
    * @todo Stream the resulting state into the page's content
    *       instead of buffering it.
    * @todo Don't directly write out hidden input field;  use an abstraction
    */
   @Override
   public void writeState(
     FacesContext context,
     StateManager.SerializedView serializedView) throws IOException
   {
     ResponseWriter rw = context.getResponseWriter();
     rw.startElement("input", null);
     rw.writeAttribute("type", "hidden", null);
     rw.writeAttribute("name", VIEW_STATE_PARAM, null);
     if (JsfUtils.IS_JSF_2_2)
     {
       rw.writeAttribute("id", StateUtils.getViewStateId(context), null);
     }

     String s = encodeSerializedViewAsString(context, serializedView);
     rw.writeAttribute("value", s, null);

     rw.endElement("input");
   }

   /**
    * A request is a postback if it contains the state parameter.
    */
   @Override
   public boolean isPostback(FacesContext context)
   {
     Map requestParams = context.getExternalContext().getRequestParameterMap();
     return requestParams.containsKey(VIEW_STATE_PARAM);
   }


   protected String encodeSerializedViewAsString(FacesContext context,
     StateManager.SerializedView serializedView) throws IOException
   {
     if ((serializedView.getState() == null) &&
         (serializedView.getStructure() instanceof String))
       return _TOKEN_PREFIX + StateUtils.construct(serializedView.getStructure(), context.getExternalContext());

     return StateUtils.construct(
             new Object[]{serializedView.getStructure(),serializedView.getState()}, context.getExternalContext());
     /*
     StringWriter sw = new StringWriter();
     BufferedWriter bw = new BufferedWriter(sw);
     Base64OutputStream b64_out = new Base64OutputStream(bw);
     GZIPOutputStream zip = new GZIPOutputStream(b64_out, _BUFFER_SIZE);
     ObjectOutput output = new ObjectOutputStream(zip);

     output.writeObject(serializedView.getStructure());
     output.writeObject(serializedView.getState());

     // this will flush the ObjectOutputStream, and close the GZIP stream, which
     // will call finish() on the GZIP stream, and then close the B64 stream,
     // which will cause it to write out the proper padding, and then close
     // the BufferedWriter which will also cause it to flush:
     output.close();

     String retVal = sw.toString();

     assert(!retVal.startsWith(_TOKEN_PREFIX));
     return retVal;*/
   }

   @Override
   public Object getTreeStructureToRestore(FacesContext context,
                                           String viewId)
   {
     Object[] view = _restoreSerializedView(context);
     if (view == null)
       return null;

     return view[0];
   }

   @Override
   public Object getComponentStateToRestore(FacesContext context)
   {
     Object[] view = _restoreSerializedView(context);
     if (view == null)
       return null;

     return view[1];
   }

   @Override
   public String getViewState(FacesContext context, Object state)
   {
     StateManager.SerializedView serializedView = _getSerializedView(context, state);
     try
     {
       return encodeSerializedViewAsString(context, serializedView);
     }
     catch (IOException e)
     {
       throw new FacesException();
     }
   }

   private StateManager.SerializedView _getSerializedView(FacesContext context, Object state)
   {

     StateManager.SerializedView view;
     if (state instanceof StateManager.SerializedView)
     {
       view = (StateManager.SerializedView) state;
     }
     else
     {
       if (state instanceof Object[])
       {
         Object[] stateArray = (Object[]) state;

         // in theory the state should be a black box, but the RI makes assumptions
         // that the state is an array of length 2
         if (stateArray.length == 2)
         {
           StateManager stateManager =
             context.getApplication().getStateManager();
           view =
               stateManager.new SerializedView(stateArray[0], stateArray[1]);
         }
         else
         {
           throw new IllegalArgumentException(_LOG.getMessage("UNEXPECTED_STATE"));
         }
       }
       else
       {
         throw new IllegalArgumentException(_LOG.getMessage("UNEXPECTED_STATE"));
       }
     }

     return view;
   }

   /**
    * Returns the State token if a valid state token is available in the request, or null if not.
    * @param external
    * @return
    */
   public static String getStateToken(ExternalContext external)
   {
     return _tokenStringFromStateString(_getStateString(external));
   }

   /**
    * Returns the State String for the request (either token or client state value)
    * @param external
    * @return
    */
   private static String _getStateString(ExternalContext external)
   {
     return external.getRequestParameterMap().get(VIEW_STATE_PARAM);
   }

   /**
    * Give a client state String, return the tokenString for it if present, or null
    */
   private static String _tokenStringFromStateString(String stateString)
   {
     if (stateString != null)
     {
       // See if we've got a token;  that'll be the case if we're
       // prefixed by _TOKEN_PREFIX
       if (stateString.startsWith(_TOKEN_PREFIX))
       {
         return stateString.substring(_TOKEN_PREFIX.length());
       }
     }

     return null;
   }


   /**
    * Restore the serialized view from the incoming request.
    * @todo ensure that the caching never gets confused by two
    *       different views being reconstituted in the same request?
    */
   @SuppressWarnings("unchecked")
   private Object[] _restoreSerializedView(
      FacesContext context)
   {
     ExternalContext external = context.getExternalContext();

     Map<String, Object> requestMap = external.getRequestMap();

     Object[] view = (Object[]) requestMap.get(_CACHED_SERIALIZED_VIEW);
     if (view == null)
     {
       String stateString = _getStateString(external);
       String tokenString = _tokenStringFromStateString(stateString);

       if (tokenString != null)
       {
         view = new Object[]{StateUtils.reconstruct(tokenString, context.getExternalContext()), null};
       }
       // Nope, let's look for a regular state field
       else
       {
         if (stateString != null)
         {
           view = (Object[]) StateUtils.reconstruct(stateString, context.getExternalContext());
           /*
           StringReader sr = new StringReader(stateString);
           BufferedReader br = new BufferedReader(sr);
           Base64InputStream b64_in = new Base64InputStream(br);


           try
           {
             ObjectInputStream ois;
             ois = new ObjectInputStreamResolveClass( new GZIPInputStream( b64_in, _BUFFER_SIZE ));

             Object structure = ois.readObject();
             Object state = ois.readObject();
             ois.close();
             view = new Object[]{structure, state};
           }
           catch (OptionalDataException ode)
           {
             _LOG.severe(ode);
           }
           catch (ClassNotFoundException cnfe)
           {
             _LOG.severe(cnfe);
           }
           catch (IOException ioe)
           {
             _LOG.severe(ioe);
           }
           */
         }
       }

       if (view != null)
         requestMap.put(_CACHED_SERIALIZED_VIEW, view);
     }

     return view;
   }


   /* Test code for dumping out the page's state
   static private void _dump(Object o)
   {
     System.out.println("DUMPING STATE");
     _dump(o, 0);
   }

   static private void _dump(Object o, int depth)
   {
     if (o instanceof Object[])
     {
       Object[] array = (Object[]) o;
       _spaces(depth);
       System.out.println("array of length " + array.length);
       for (int i = 0; i < array.length; i++)
         _dump(array[i], depth + 1);
     }
     else
     {
       _spaces(depth);
       System.out.println(o);
     }
   }

   static private void _spaces(int count)
   {
     int i = 0;
     for (; i + 5 < count; i += 5)
       System.out.print("     ");
     for (; i < count; i++)
       System.out.print(" ");
   }

   */

   static private final int _BUFFER_SIZE = 2048;
   static private final String _CACHED_SERIALIZED_VIEW =
     "org.apache.myfaces.trinidadinternal.renderkit.CACHED_SERIALIZED_VIEW";

   // Exclamation marks are not legit Base64 characters;  only
   // A-Z, a-z, 0-9, +, /, and = can ever show up.
   static private final String _TOKEN_PREFIX = "!";

   static private final TrinidadLogger _LOG = TrinidadLogger.createTrinidadLogger(CoreResponseStateManager.class);
 }
	/*
	* 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.myfaces.trinidadinternal.renderkit.core;

	import java.io.IOException;

	import java.util.Map;

	import javax.faces.FacesException;
	import javax.faces.application.StateManager;
	import javax.faces.context.ExternalContext;
	import javax.faces.context.FacesContext;
	import javax.faces.context.ResponseWriter;
	import javax.faces.render.ResponseStateManager;

	import org.apache.myfaces.trinidad.logging.TrinidadLogger;
	import org.apache.myfaces.trinidadinternal.application.StateManagerImpl;
	import org.apache.myfaces.trinidadinternal.util.JsfUtils;
	import org.apache.myfaces.trinidadinternal.util.StateUtils;

	/**
	* ResponseStateManager implementation for the Core RenderKit.
	* <p>
	*/
	public class CoreResponseStateManager extends ResponseStateManager
	{

	@Override
	public Object getState(FacesContext context, String viewId)
	{
	// TODO see doc in StateManagerImpl.restoreView
	// (search for StateManagerImpl.RESPONSE_STATE_MANAGER_STATE_KEY) to see doc
	// about what's going on here
	Object state = context.getExternalContext().getRequestMap().get(
	StateManagerImpl.RESPONSE_STATE_MANAGER_STATE_KEY);

	if (state != null)
	return state;
	else
	return super.getState(context, viewId);
	}


	/**
	* Name of the form field that encodes the UI state.
	*/
	static public final String FORM_FIELD_NAME = "org.apache.myfaces.trinidad.faces.FORM";

	/**
	* Write the state into the page.
	* @todo Stream the resulting state into the page's content
	* instead of buffering it.
	* @todo Don't directly write out hidden input field; use an abstraction
	*/
	@Override
	public void writeState(
	FacesContext context,
	StateManager.SerializedView serializedView) throws IOException
	{
	ResponseWriter rw = context.getResponseWriter();
	rw.startElement("input", null);
	rw.writeAttribute("type", "hidden", null);
	rw.writeAttribute("name", VIEW_STATE_PARAM, null);
	if (JsfUtils.IS_JSF_2_2)
	{
	rw.writeAttribute("id", StateUtils.getViewStateId(context), null);
	}

	String s = encodeSerializedViewAsString(context, serializedView);
	rw.writeAttribute("value", s, null);

	rw.endElement("input");
	}

	/**
	* A request is a postback if it contains the state parameter.
	*/
	@Override
	public boolean isPostback(FacesContext context)
	{
	Map requestParams = context.getExternalContext().getRequestParameterMap();
	return requestParams.containsKey(VIEW_STATE_PARAM);
	}


	protected String encodeSerializedViewAsString(FacesContext context,
	StateManager.SerializedView serializedView) throws IOException
	{
	if ((serializedView.getState() == null) &&
	(serializedView.getStructure() instanceof String))
	return _TOKEN_PREFIX + StateUtils.construct(serializedView.getStructure(), context.getExternalContext());

	return StateUtils.construct(
	new Object[]{serializedView.getStructure(),serializedView.getState()}, context.getExternalContext());
	/*
	StringWriter sw = new StringWriter();
	BufferedWriter bw = new BufferedWriter(sw);
	Base64OutputStream b64_out = new Base64OutputStream(bw);
	GZIPOutputStream zip = new GZIPOutputStream(b64_out, _BUFFER_SIZE);
	ObjectOutput output = new ObjectOutputStream(zip);

	output.writeObject(serializedView.getStructure());
	output.writeObject(serializedView.getState());

	// this will flush the ObjectOutputStream, and close the GZIP stream, which
	// will call finish() on the GZIP stream, and then close the B64 stream,
	// which will cause it to write out the proper padding, and then close
	// the BufferedWriter which will also cause it to flush:
	output.close();

	String retVal = sw.toString();

	assert(!retVal.startsWith(_TOKEN_PREFIX));
	return retVal;*/
	}

	@Override
	public Object getTreeStructureToRestore(FacesContext context,
	String viewId)
	{
	Object[] view = _restoreSerializedView(context);
	if (view == null)
	return null;

	return view[0];
	}

	@Override
	public Object getComponentStateToRestore(FacesContext context)
	{
	Object[] view = _restoreSerializedView(context);
	if (view == null)
	return null;

	return view[1];
	}

	@Override
	public String getViewState(FacesContext context, Object state)
	{
	StateManager.SerializedView serializedView = _getSerializedView(context, state);
	try
	{
	return encodeSerializedViewAsString(context, serializedView);
	}
	catch (IOException e)
	{
	throw new FacesException();
	}
	}

	private StateManager.SerializedView _getSerializedView(FacesContext context, Object state)
	{

	StateManager.SerializedView view;
	if (state instanceof StateManager.SerializedView)
	{
	view = (StateManager.SerializedView) state;
	}
	else
	{
	if (state instanceof Object[])
	{
	Object[] stateArray = (Object[]) state;

	// in theory the state should be a black box, but the RI makes assumptions
	// that the state is an array of length 2
	if (stateArray.length == 2)
	{
	StateManager stateManager =
	context.getApplication().getStateManager();
	view =
	stateManager.new SerializedView(stateArray[0], stateArray[1]);
	}
	else
	{
	throw new IllegalArgumentException(_LOG.getMessage("UNEXPECTED_STATE"));
	}
	}
	else
	{
	throw new IllegalArgumentException(_LOG.getMessage("UNEXPECTED_STATE"));
	}
	}

	return view;
	}

	/**
	* Returns the State token if a valid state token is available in the request, or null if not.
	* @param external
	* @return
	*/
	public static String getStateToken(ExternalContext external)
	{
	return _tokenStringFromStateString(_getStateString(external));
	}

	/**
	* Returns the State String for the request (either token or client state value)
	* @param external
	* @return
	*/
	private static String _getStateString(ExternalContext external)
	{
	return external.getRequestParameterMap().get(VIEW_STATE_PARAM);
	}

	/**
	* Give a client state String, return the tokenString for it if present, or null
	*/
	private static String _tokenStringFromStateString(String stateString)
	{
	if (stateString != null)
	{
	// See if we've got a token; that'll be the case if we're
	// prefixed by _TOKEN_PREFIX
	if (stateString.startsWith(_TOKEN_PREFIX))
	{
	return stateString.substring(_TOKEN_PREFIX.length());
	}
	}

	return null;
	}


	/**
	* Restore the serialized view from the incoming request.
	* @todo ensure that the caching never gets confused by two
	* different views being reconstituted in the same request?
	*/
	@SuppressWarnings("unchecked")
	private Object[] _restoreSerializedView(
	FacesContext context)
	{
	ExternalContext external = context.getExternalContext();

	Map<String, Object> requestMap = external.getRequestMap();

	Object[] view = (Object[]) requestMap.get(_CACHED_SERIALIZED_VIEW);
	if (view == null)
	{
	String stateString = _getStateString(external);
	String tokenString = _tokenStringFromStateString(stateString);

	if (tokenString != null)
	{
	view = new Object[]{StateUtils.reconstruct(tokenString, context.getExternalContext()), null};
	}
	// Nope, let's look for a regular state field
	else
	{
	if (stateString != null)
	{
	view = (Object[]) StateUtils.reconstruct(stateString, context.getExternalContext());
	/*
	StringReader sr = new StringReader(stateString);
	BufferedReader br = new BufferedReader(sr);
	Base64InputStream b64_in = new Base64InputStream(br);


	try
	{
	ObjectInputStream ois;
	ois = new ObjectInputStreamResolveClass( new GZIPInputStream( b64_in, _BUFFER_SIZE ));

	Object structure = ois.readObject();
	Object state = ois.readObject();
	ois.close();
	view = new Object[]{structure, state};
	}
	catch (OptionalDataException ode)
	{
	_LOG.severe(ode);
	}
	catch (ClassNotFoundException cnfe)
	{
	_LOG.severe(cnfe);
	}
	catch (IOException ioe)
	{
	_LOG.severe(ioe);
	}
	*/
	}
	}

	if (view != null)
	requestMap.put(_CACHED_SERIALIZED_VIEW, view);
	}

	return view;
	}




	/* Test code for dumping out the page's state
	static private void _dump(Object o)
	{
	System.out.println("DUMPING STATE");
	_dump(o, 0);
	}

	static private void _dump(Object o, int depth)
	{
	if (o instanceof Object[])
	{
	Object[] array = (Object[]) o;
	_spaces(depth);
	System.out.println("array of length " + array.length);
	for (int i = 0; i < array.length; i++)
	_dump(array[i], depth + 1);
	}
	else
	{
	_spaces(depth);
	System.out.println(o);
	}
	}

	static private void _spaces(int count)
	{
	int i = 0;
	for (; i + 5 < count; i += 5)
	System.out.print(" ");
	for (; i < count; i++)
	System.out.print(" ");
	}

	*/

	static private final int _BUFFER_SIZE = 2048;
	static private final String _CACHED_SERIALIZED_VIEW =
	"org.apache.myfaces.trinidadinternal.renderkit.CACHED_SERIALIZED_VIEW";

	// Exclamation marks are not legit Base64 characters; only
	// A-Z, a-z, 0-9, +, /, and = can ever show up.
	static private final String _TOKEN_PREFIX = "!";

	static private final TrinidadLogger _LOG = TrinidadLogger.createTrinidadLogger(CoreResponseStateManager.class);
	}