com.sun.faces.renderkit.StateHelper Maven / Gradle / Ivy
Show all versions of javax.faces Show documentation
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2012 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package com.sun.faces.renderkit;
import java.io.IOException;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.render.ResponseStateManager;
import javax.faces.render.RenderKitFactory;
import com.sun.faces.spi.SerializationProviderFactory;
import com.sun.faces.spi.SerializationProvider;
import com.sun.faces.config.WebConfiguration;
import static com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter.CompressViewState;
import static com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter.EnableViewStateIdRendering;
import static com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter.AutoCompleteOffOnViewState;
/**
* Common code for the default StateHelper
implementations.
*/
public abstract class StateHelper {
/**
*
* State hidden field start. Content after this is the actual
* state representation followed by the {@link #STATE_FIELD_END}.
*
*
* @see {@link com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter#EnableViewStateIdRendering}
*/
protected static final char[] STATE_FIELD_START =
("
* Alternate hidden field to generate W3C valid XHTML. This version
* includes no id attribute. This version will be used when the
* EnableViewStateIdRendering
is disabled.
*
*
* @see {@link com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter#EnableViewStateIdRendering}
*/
protected static final char[] STATE_FIELD_START_NO_ID =
("
* The end of the hidden state field.
*
*/
protected static final char[] STATE_FIELD_END =
"\" />".toCharArray();
/**
*
* The end of the hidden state field.
*
*/
protected static final char[] STATE_FIELD_AUTOCOMPLETE_END =
"\" autocomplete=\"off\" />".toCharArray();
/**
*
* Factory for serialization streams. These are pluggable via
* the WebConfiguration.WebContextInitParameter#SerializationProviderClass.
*
*/
protected SerializationProvider serialProvider;
/**
*
* Access to the context init parameters that configure this application.
*
*/
protected WebConfiguration webConfig;
/**
*
* Flag indicating whether or not view state should be compressed to reduce
* the memory/bandwidth footprint. This option is common to both types
* of state saving.
*
*/
protected boolean compressViewState;
/**
* This will be used the by the different StateHelper
implementations
* when writing the start of the state field. This value of this field is
* determined by the value of the {@link com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter#EnableViewStateIdRendering}
*/
protected char[] stateFieldStart;
/**
* This will be used the by the different StateHelper
implementations
* when writing the end of the state field. This value of this field is
* determined by the value of the {@link com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter#AutoCompleteOffOnViewState}
*/
protected char[] stateFieldEnd;
// ------------------------------------------------------------ Constructors
/**
* Constructs a new StateHelper
instance.
*/
public StateHelper() {
FacesContext ctx = FacesContext.getCurrentInstance();
serialProvider = SerializationProviderFactory
.createInstance(ctx.getExternalContext());
webConfig = WebConfiguration.getInstance(ctx.getExternalContext());
compressViewState = webConfig.isOptionEnabled(CompressViewState);
stateFieldStart = (webConfig.isOptionEnabled(EnableViewStateIdRendering)
? STATE_FIELD_START
: STATE_FIELD_START_NO_ID);
stateFieldEnd = (webConfig.isOptionEnabled(AutoCompleteOffOnViewState)
? STATE_FIELD_AUTOCOMPLETE_END
: STATE_FIELD_END);
if (serialProvider == null) {
serialProvider = SerializationProviderFactory
.createInstance(FacesContext
.getCurrentInstance().getExternalContext());
}
}
// ---------------------------------------------------------- Public Methods
/**
*
* Functionally similar to ResponseStateManager#writeState(FacesContext, Object)
* with an option to write the state directly to the provided StringBuilder
* without sending any markup to the client.
*
*
* @see ResponseStateManager#writeState(javax.faces.context.FacesContext, java.lang.Object)
*/
public abstract void writeState(FacesContext ctx,
Object state,
StringBuilder stateCapture)
throws IOException;
/**
* @see javax.faces.render.ResponseStateManager#getState(javax.faces.context.FacesContext, String)
*/
public abstract Object getState(FacesContext ctx, String viewId)
throws IOException;
// ------------------------------------------------------- Protected Methods
/**
* Get our view state from this request
*
* @param context the FacesContext
for the current request
*
* @return the view state from this request
*/
protected static String getStateParamValue(FacesContext context) {
String pValue = context.getExternalContext().getRequestParameterMap().
get(ResponseStateManager.VIEW_STATE_PARAM);
if (pValue != null && pValue.length() == 0) {
pValue = null;
}
return pValue;
}
/**
*
* If a custom RenderKit
is used, write out the ID
* of the RenderKit
out as a hidden field. This will be used
* when restoring the view state.
*
* @param context the FacesContext
for the current request
* @param writer the ResponseWriter
to write to
* @throws IOException if an error occurs writing to the client
*/
protected void writeRenderKitIdField(FacesContext context,
ResponseWriter writer)
throws IOException {
String result = context.getApplication().getDefaultRenderKitId();
if (result != null
&& !RenderKitFactory.HTML_BASIC_RENDER_KIT.equals(result)) {
writer.startElement("input", context.getViewRoot());
writer.writeAttribute("type", "hidden", "type");
writer.writeAttribute("name",
ResponseStateManager.RENDER_KIT_ID_PARAM,
"name");
writer.writeAttribute("value",
result,
"value");
writer.endElement("input");
}
}
}