/*
* 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.shared.application;
import java.net.MalformedURLException;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.faces.application.ProjectStage;
import javax.faces.application.ViewHandler;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.faces.view.ViewDeclarationLanguage;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFWebConfigParam;
import org.apache.myfaces.shared.util.WebConfigParamUtils;
/**
* A ViewHandlerSupport implementation for use with standard Java Servlet engines,
* ie an engine that supports javax.servlet, and uses a standard web.xml file.
*
* @author Mathias Broekelmann (latest modification by $Author: lu4242 $)
* @version $Revision: 887436 $ $Date: 2009-12-04 16:11:25 -0700 (Fri, 04 Dec 2009) $
*/
public class DefaultViewHandlerSupport implements ViewHandlerSupport
{
/**
* Identifies the FacesServlet mapping in the current request map.
*/
private static final String CACHED_SERVLET_MAPPING =
DefaultViewHandlerSupport.class.getName() + ".CACHED_SERVLET_MAPPING";
//private static final Log log = LogFactory.getLog(DefaultViewHandlerSupport.class);
private static final Logger log = Logger.getLogger(DefaultViewHandlerSupport.class.getName());
/**
* Controls the size of the cache used to "remember" if a view exists or not.
*/
@JSFWebConfigParam(defaultValue = "500", since = "2.0.2",
desc="Controls the size of the cache used to 'remember' if a view exists or not.")
private static final String CHECKED_VIEWID_CACHE_SIZE_ATTRIBUTE = "org.apache.myfaces.CHECKED_VIEWID_CACHE_SIZE";
private static final int CHECKED_VIEWID_CACHE_DEFAULT_SIZE = 500;
/**
* Enable or disable a cache used to "remember" if a view exists or not and reduce the impact of
* sucesive calls to ExternalContext.getResource().
*/
@JSFWebConfigParam(defaultValue = "true", since = "2.0.2",
desc="Enable or disable a cache used to 'remember' if a view exists or not and reduce the impact of sucesive calls to ExternalContext.getResource().")
private static final String CHECKED_VIEWID_CACHE_ENABLED_ATTRIBUTE = "org.apache.myfaces.CHECKED_VIEWID_CACHE_ENABLED";
private static final boolean CHECKED_VIEWID_CACHE_ENABLED_DEFAULT = true;
private Map<String, Boolean> _checkedViewIdMap = null;
private Boolean _checkedViewIdCacheEnabled = null;
public String calculateViewId(FacesContext context, String viewId)
{
//If no viewId found, don't try to derive it, just continue.
if (viewId == null)
{
return null;
}
FacesServletMapping mapping = getFacesServletMapping(context);
if (mapping == null || mapping.isExtensionMapping())
{
viewId = handleSuffixMapping(context, viewId);
}
else if(mapping.isPrefixMapping())
{
viewId = handlePrefixMapping(viewId,mapping.getPrefix());
}
else if (viewId != null && mapping.getUrlPattern().startsWith(viewId))
{
throw new InvalidViewIdException(viewId);
}
//if(viewId != null)
//{
// return (checkResourceExists(context,viewId) ? viewId : null);
//}
return viewId; // return null if no physical resource exists
}
public String calculateAndCheckViewId(FacesContext context, String viewId)
{
//If no viewId found, don't try to derive it, just continue.
if (viewId == null)
{
return null;
}
FacesServletMapping mapping = getFacesServletMapping(context);
if (mapping == null || mapping.isExtensionMapping())
{
viewId = handleSuffixMapping(context, viewId);
}
else if(mapping.isPrefixMapping())
{
viewId = handlePrefixMapping(viewId,mapping.getPrefix());
if(viewId != null)
{
return (checkResourceExists(context,viewId) ? viewId : null);
}
}
else if (viewId != null && mapping.getUrlPattern().startsWith(viewId))
{
throw new InvalidViewIdException(viewId);
}
else
{
if(viewId != null)
{
return (checkResourceExists(context,viewId) ? viewId : null);
}
}
return viewId; // return null if no physical resource exists
}
public String calculateActionURL(FacesContext context, String viewId)
{
if (viewId == null || !viewId.startsWith("/"))
{
throw new IllegalArgumentException("ViewId must start with a '/': " + viewId);
}
FacesServletMapping mapping = getFacesServletMapping(context);
ExternalContext externalContext = context.getExternalContext();
String contextPath = externalContext.getRequestContextPath();
StringBuilder builder = new StringBuilder(contextPath);
if (mapping != null)
{
if (mapping.isExtensionMapping())
{
String[] contextSuffixes = getContextSuffix(context);
boolean founded = false;
for (String contextSuffix : contextSuffixes)
{
if (viewId.endsWith(contextSuffix))
{
builder.append(viewId.substring(0, viewId.indexOf(contextSuffix)));
builder.append(mapping.getExtension());
founded = true;
break;
}
}
if (!founded)
{
if(viewId.lastIndexOf(".") != -1 )
{
builder.append(viewId.substring(0,viewId.lastIndexOf(".")));
}
else
{
builder.append(viewId);
}
builder.append(contextSuffixes[0]);
}
}
else
{
builder.append(mapping.getPrefix());
builder.append(viewId);
}
}
else
{
builder.append(viewId);
}
String calculatedActionURL = builder.toString();
if (log.isLoggable(Level.FINEST))
{
log.finest("Calculated actionURL: '" + calculatedActionURL + "' for viewId: '" + viewId + "'");
}
return calculatedActionURL;
}
/**
* Read the web.xml file that is in the classpath and parse its internals to
* figure out how the FacesServlet is mapped for the current webapp.
*/
protected FacesServletMapping getFacesServletMapping(FacesContext context)
{
Map<String, Object> requestMap = context.getExternalContext().getRequestMap();
// Has the mapping already been determined during this request?
if (!requestMap.containsKey(CACHED_SERVLET_MAPPING))
{
ExternalContext externalContext = context.getExternalContext();
FacesServletMapping mapping =
calculateFacesServletMapping(
externalContext.getRequestServletPath(),
externalContext.getRequestPathInfo());
requestMap.put(CACHED_SERVLET_MAPPING, mapping);
}
return (FacesServletMapping) requestMap.get(CACHED_SERVLET_MAPPING);
}
/**
* Determines the mapping of the FacesServlet in the web.xml configuration
* file. However, there is no need to actually parse this configuration file
* as runtime information is sufficient.
*
* @param servletPath The servletPath of the current request
* @param pathInfo The pathInfo of the current request
* @return the mapping of the FacesServlet in the web.xml configuration file
*/
protected static FacesServletMapping calculateFacesServletMapping(
String servletPath, String pathInfo)
{
if (pathInfo != null)
{
// If there is a "extra path", it's definitely no extension mapping.
// Now we just have to determine the path which has been specified
// in the url-pattern, but that's easy as it's the same as the
// current servletPath. It doesn't even matter if "/*" has been used
// as in this case the servletPath is just an empty string according
// to the Servlet Specification (SRV 4.4).
return FacesServletMapping.createPrefixMapping(servletPath);
}
else
{
// In the case of extension mapping, no "extra path" is available.
// Still it's possible that prefix-based mapping has been used.
// Actually, if there was an exact match no "extra path"
// is available (e.g. if the url-pattern is "/faces/*"
// and the request-uri is "/context/faces").
int slashPos = servletPath.lastIndexOf('/');
int extensionPos = servletPath.lastIndexOf('.');
if (extensionPos > -1 && extensionPos > slashPos)
{
String extension = servletPath.substring(extensionPos);
return FacesServletMapping.createExtensionMapping(extension);
}
else
{
// There is no extension in the given servletPath and therefore
// we assume that it's an exact match using prefix-based mapping.
return FacesServletMapping.createPrefixMapping(servletPath);
}
}
}
protected String[] getContextSuffix(FacesContext context)
{
String defaultSuffix = context.getExternalContext().getInitParameter(ViewHandler.DEFAULT_SUFFIX_PARAM_NAME);
if (defaultSuffix == null)
{
defaultSuffix = ViewHandler.DEFAULT_SUFFIX;
}
return defaultSuffix.split(" ");
}
protected String getFaceletsContextSuffix(FacesContext context)
{
String defaultSuffix = context.getExternalContext().getInitParameter(ViewHandler.FACELETS_SUFFIX_PARAM_NAME);
if (defaultSuffix == null)
{
defaultSuffix = ViewHandler.DEFAULT_FACELETS_SUFFIX;
}
return defaultSuffix;
}
protected String[] getFaceletsViewMappings(FacesContext context)
{
String faceletsViewMappings= context.getExternalContext().getInitParameter(ViewHandler.FACELETS_VIEW_MAPPINGS_PARAM_NAME);
if(faceletsViewMappings == null) //consider alias facelets.VIEW_MAPPINGS
{
faceletsViewMappings= context.getExternalContext().getInitParameter("facelets.VIEW_MAPPINGS");
}
return faceletsViewMappings == null ? null : faceletsViewMappings.split(";");
}
/**
* Return the normalized viewId according to the algorithm specified in 7.5.2
* by stripping off any number of occurrences of the prefix mapping from the viewId.
* <p/>
* For example, both /faces/view.xhtml and /faces/faces/faces/view.xhtml would both return view.xhtml
* F
*/
protected String handlePrefixMapping(String viewId, String prefix)
{
// If prefix mapping (such as "/faces/*") is used for FacesServlet,
// normalize the viewId according to the following
// algorithm, or its semantic equivalent, and return it.
// Remove any number of occurrences of the prefix mapping from the viewId.
// For example, if the incoming value was /faces/faces/faces/view.xhtml
// the result would be simply view.xhtml.
if ("".equals(prefix))
{
// if prefix is an empty string (Spring environment), we let it be "//"
// in order to prevent an infinite loop in uri.startsWith(-emptyString-).
// Furthermore a prefix of "//" is just another double slash prevention.
prefix = "//";
}
else
{
// need to make sure its really /faces/* and not /facesPage.xhtml
prefix = prefix + '/';
}
String uri = viewId;
while (uri.startsWith(prefix) || uri.startsWith("//"))
{
if (uri.startsWith(prefix))
{
// cut off only /faces, leave the trailing '/' char for the next iteration
uri = uri.substring(prefix.length() - 1);
}
else
{
// uri starts with '//' --> cut off the leading slash, leaving
// the second slash to compare for the next iteration
uri = uri.substring(1);
}
}
//now delete any remaining leading '/'
// TODO: CJH: I don't think this is correct, considering that getActionURL() expects everything to
// start with '/', and in the suffix case we only mess with the suffix and leave leading
// slashes alone. Please review...
/*if(uri.startsWith("/"))
{
uri = uri.substring(1);
}*/
return uri;
}
/**
* Return the viewId with any non-standard suffix stripped off and replaced with
* the default suffix configured for the specified context.
* <p/>
* For example, an input parameter of "/foo.jsf" may return "/foo.jsp".
*/
protected String handleSuffixMapping(FacesContext context, String requestViewId)
{
String[] faceletsViewMappings = getFaceletsViewMappings(context);
String[] jspDefaultSuffixes = getContextSuffix(context);
int slashPos = requestViewId.lastIndexOf('/');
int extensionPos = requestViewId.lastIndexOf('.');
//Try to locate any resource that match with the expected id
for (String defaultSuffix : jspDefaultSuffixes)
{
StringBuilder builder = new StringBuilder(requestViewId);
if (extensionPos > -1 && extensionPos > slashPos)
{
builder.replace(extensionPos, requestViewId.length(), defaultSuffix);
}
else
{
builder.append(defaultSuffix);
}
String candidateViewId = builder.toString();
if( faceletsViewMappings != null && faceletsViewMappings.length > 0 )
{
for (String mapping : faceletsViewMappings)
{
if(mapping.startsWith("/"))
{
continue; //skip this entry, its a prefix mapping
}
if(mapping.equals(candidateViewId))
{
return candidateViewId;
}
if(mapping.startsWith(".")) //this is a wildcard entry
{
builder.setLength(0); //reset/reuse the builder object
builder.append(candidateViewId);
builder.replace(candidateViewId.lastIndexOf('.'), candidateViewId.length(), mapping);
String tempViewId = builder.toString();
if(checkResourceExists(context,tempViewId))
return tempViewId;
}
}
}
// forced facelets mappings did not match or there were no entries in faceletsViewMappings array
if(checkResourceExists(context,candidateViewId))
return candidateViewId;
}
//jsp suffixes didn't match, try facelets suffix
String faceletsDefaultSuffix = this.getFaceletsContextSuffix(context);
if (faceletsDefaultSuffix != null)
{
for (String defaultSuffix : jspDefaultSuffixes)
{
if (faceletsDefaultSuffix.equals(defaultSuffix))
{
faceletsDefaultSuffix = null;
break;
}
}
}
if (faceletsDefaultSuffix != null)
{
StringBuilder builder = new StringBuilder(requestViewId);
if (extensionPos > -1 && extensionPos > slashPos)
{
builder.replace(extensionPos, requestViewId.length(), faceletsDefaultSuffix);
}
else
{
builder.append(faceletsDefaultSuffix);
}
String candidateViewId = builder.toString();
if(checkResourceExists(context,candidateViewId))
return candidateViewId;
}
// Otherwise, if a physical resource exists with the name requestViewId let that value be viewId.
if(checkResourceExists(context,requestViewId))
return requestViewId;
//Otherwise return null.
return null;
}
protected boolean checkResourceExists(FacesContext context, String viewId)
{
try
{
if (isCheckedViewIdCachingEnabled(context))
{
Boolean resourceExists = getCheckedViewIDMap(context).get(
viewId);
if (resourceExists == null)
{
ViewDeclarationLanguage vdl = context.getApplication().getViewHandler().getViewDeclarationLanguage(context, viewId);
if (vdl != null)
{
resourceExists = vdl.viewExists(context, viewId);
}
else
{
// Fallback to default strategy
resourceExists = context.getExternalContext().getResource(
viewId) != null;
}
getCheckedViewIDMap(context).put(viewId, resourceExists);
}
return resourceExists;
}
else
{
ViewDeclarationLanguage vdl = context.getApplication().getViewHandler().getViewDeclarationLanguage(context, viewId);
if (vdl != null)
{
if (vdl.viewExists(context, viewId))
{
return true;
}
}
else
{
// Fallback to default strategy
if (context.getExternalContext().getResource(viewId) != null)
{
return true;
}
}
}
}
catch(MalformedURLException e)
{
//ignore and move on
}
return false;
}
private Map<String, Boolean> getCheckedViewIDMap(FacesContext context)
{
if (_checkedViewIdMap == null)
{
_checkedViewIdMap = Collections.synchronizedMap(new _CheckedViewIDMap<String, Boolean>(getViewIDCacheMaxSize(context)));
}
return _checkedViewIdMap;
}
private boolean isCheckedViewIdCachingEnabled(FacesContext context)
{
if (_checkedViewIdCacheEnabled == null)
{
// first, check if the ProjectStage is development and skip caching in this case
if (context.isProjectStage(ProjectStage.Development))
{
_checkedViewIdCacheEnabled = Boolean.FALSE;
}
else
{
// in all ohter cases, make sure that the cache is not explicitly disabled via context param
_checkedViewIdCacheEnabled = WebConfigParamUtils.getBooleanInitParameter(context.getExternalContext(),
CHECKED_VIEWID_CACHE_ENABLED_ATTRIBUTE,
CHECKED_VIEWID_CACHE_ENABLED_DEFAULT);
}
if (log.isLoggable(Level.FINE))
{
log.log(Level.FINE, "MyFaces ViewID Caching Enabled="
+ _checkedViewIdCacheEnabled);
}
}
return _checkedViewIdCacheEnabled;
}
private int getViewIDCacheMaxSize(FacesContext context)
{
ExternalContext externalContext = context.getExternalContext();
return WebConfigParamUtils.getIntegerInitParameter(externalContext,
CHECKED_VIEWID_CACHE_SIZE_ATTRIBUTE, CHECKED_VIEWID_CACHE_DEFAULT_SIZE);
}
private class _CheckedViewIDMap<K, V> extends LinkedHashMap<K, V>
{
private static final long serialVersionUID = 1L;
private int maxCapacity;
public _CheckedViewIDMap(int cacheSize)
{
// create map at max capacity and 1.1 load factor to avoid rehashing
super(cacheSize + 1, 1.1f, true);
maxCapacity = cacheSize;
}
@Override
protected boolean removeEldestEntry(Map.Entry<K, V> eldest)
{
return size() > maxCapacity;
}
}
}