runtime/org.argeo.slc.server/src/main/java/org/argeo/slc/web/mvc/XsltMarshallerViewResolver.java

   1 /*
   2  * Copyright (C) 2007-2012 Mathieu Baudier
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.slc.web.mvc;
  17
  18 import java.io.IOException;
  19 import java.util.Map;
  20 import java.util.TreeMap;
  21
  22 import javax.xml.transform.Source;
  23 import javax.xml.transform.TransformerException;
  24 import javax.xml.transform.URIResolver;
  25 import javax.xml.transform.stream.StreamSource;
  26
  27 import org.apache.commons.logging.Log;
  28 import org.apache.commons.logging.LogFactory;
  29 import org.argeo.slc.SlcException;
  30 import org.springframework.core.io.Resource;
  31 import org.springframework.oxm.Marshaller;
  32 import org.springframework.web.servlet.view.AbstractUrlBasedView;
  33 import org.springframework.web.servlet.view.xslt.XsltViewResolver;
  34
  35 /**
  36  * Xslt View resolver implementing URI resolver as well.
  37  *
  38  * @see URIResolver
  39  * @see XsltViewResolver
  40  */
  41 public class XsltMarshallerViewResolver extends XsltViewResolver implements
  42                 URIResolver {
  43         private final static Log log = LogFactory
  44                         .getLog(XsltMarshallerViewResolver.class);
  45
  46         private Marshaller marshaller;
  47         private Map<String, Source> cacheUriResolver = new TreeMap<String, Source>();
  48
  49         public XsltMarshallerViewResolver() {
  50                 setUriResolver(this);
  51         }
  52
  53         @Override
  54         protected AbstractUrlBasedView buildView(String viewName) throws Exception {
  55                 AbstractUrlBasedView viewT = super.buildView(viewName);
  56                 XsltMarshallerView view = (XsltMarshallerView) viewT;
  57                 view.setMarshaller(marshaller);
  58                 return view;
  59         }
  60
  61         public void setMarshaller(Marshaller marshaller) {
  62                 this.marshaller = marshaller;
  63         }
  64
  65         public Source resolve(String href, String base) throws TransformerException {
  66                 if (log.isTraceEnabled())
  67                         log.trace("Resolve URI for href=" + href + " base=" + base);
  68
  69                 Source res = null;
  70                 if (isCache())
  71                         res = cacheUriResolver.get(href);
  72
  73                 if (res == null)
  74                         res = getStylesheetSource(href);
  75
  76                 if (res == null)
  77                         res = getStylesheetSource(getPrefix() + href);
  78
  79                 if (res == null)
  80                         throw new SlcException("Can't resolve URI for href=" + href
  81                                         + " base=" + base);
  82
  83                 if (isCache() && !cacheUriResolver.containsKey(href))
  84                         cacheUriResolver.put(href, res);
  85
  86                 return res;
  87         }
  88
  89         protected Source getStylesheetSource(String url) {
  90                 if (log.isDebugEnabled()) {
  91                         log.debug("Loading XSLT stylesheet from '" + url + "'");
  92                 }
  93                 try {
  94                         final Resource stylesheetResource = getApplicationContext()
  95                                         .getResource(url);
  96                         String systemId = url.substring(0, url.lastIndexOf('/') + 1);
  97                         return new StreamSource(stylesheetResource.getInputStream(),
  98                                         systemId);
  99                 } catch (IOException e) {
 100                         if (log.isTraceEnabled())
 101                                 log.trace("Cannot load stylesheet " + url, e);
 102                         return null;
 103                 }
 104         }
 105
 106 }