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

   1 package org.argeo.slc.web.mvc;
   2
   3 import java.io.IOException;
   4 import java.util.Map;
   5 import java.util.TreeMap;
   6
   7 import javax.xml.transform.Source;
   8 import javax.xml.transform.TransformerException;
   9 import javax.xml.transform.URIResolver;
  10 import javax.xml.transform.stream.StreamSource;
  11
  12 import org.apache.commons.logging.Log;
  13 import org.apache.commons.logging.LogFactory;
  14 import org.argeo.slc.SlcException;
  15 import org.springframework.core.io.Resource;
  16 import org.springframework.oxm.Marshaller;
  17 import org.springframework.web.servlet.view.AbstractUrlBasedView;
  18 import org.springframework.web.servlet.view.xslt.XsltViewResolver;
  19
  20 /**
  21  * Xslt View resolver implementing URI resolver as well.
  22  *
  23  * @see URIResolver
  24  * @see XsltViewResolver
  25  */
  26 public class XsltMarshallerViewResolver extends XsltViewResolver implements
  27                 URIResolver {
  28         private final static Log log = LogFactory
  29                         .getLog(XsltMarshallerViewResolver.class);
  30
  31         private Marshaller marshaller;
  32         private Map<String, Source> cacheUriResolver = new TreeMap<String, Source>();
  33
  34         public XsltMarshallerViewResolver() {
  35                 setUriResolver(this);
  36         }
  37
  38         @Override
  39         protected AbstractUrlBasedView buildView(String viewName) throws Exception {
  40                 AbstractUrlBasedView viewT = super.buildView(viewName);
  41                 XsltMarshallerView view = (XsltMarshallerView) viewT;
  42                 view.setMarshaller(marshaller);
  43                 return view;
  44         }
  45
  46         public void setMarshaller(Marshaller marshaller) {
  47                 this.marshaller = marshaller;
  48         }
  49
  50         public Source resolve(String href, String base) throws TransformerException {
  51                 if (log.isTraceEnabled())
  52                         log.trace("Resolve URI for href=" + href + " base=" + base);
  53
  54                 Source res = null;
  55                 if (isCache())
  56                         res = cacheUriResolver.get(href);
  57
  58                 if (res == null)
  59                         res = getStylesheetSource(href);
  60
  61                 if (res == null)
  62                         res = getStylesheetSource(getPrefix() + href);
  63
  64                 if (res == null)
  65                         throw new SlcException("Can't resolve URI for href=" + href
  66                                         + " base=" + base);
  67
  68                 if (isCache() && !cacheUriResolver.containsKey(href))
  69                         cacheUriResolver.put(href, res);
  70
  71                 return res;
  72         }
  73
  74         protected Source getStylesheetSource(String url) {
  75                 if (log.isDebugEnabled()) {
  76                         log.debug("Loading XSLT stylesheet from '" + url + "'");
  77                 }
  78                 try {
  79                         final Resource stylesheetResource = getApplicationContext()
  80                                         .getResource(url);
  81                         String systemId = url.substring(0, url.lastIndexOf('/') + 1);
  82                         return new StreamSource(stylesheetResource.getInputStream(),
  83                                         systemId);
  84                 } catch (IOException e) {
  85                         if (log.isTraceEnabled())
  86                                 log.trace("Cannot load stylesheet " + url, e);
  87                         return null;
  88                 }
  89         }
  90
  91 }