Rename GCR to ACR.

[lgpl/argeo-commons.git] / org.argeo.cms / src / org / argeo / cms / acr / xml / DomContentProvider.java

diff --git a/org.argeo.cms/src/org/argeo/cms/acr/xml/DomContentProvider.java b/org.argeo.cms/src/org/argeo/cms/acr/xml/DomContentProvider.java
new file mode 100644 (file)
index 0000000..c5fde8d
--- /dev/null
+++ b/org.argeo.cms/src/org/argeo/cms/acr/xml/DomContentProvider.java
@@ -0,0 +1,99 @@
+package org.argeo.cms.acr.xml;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+
+import javax.xml.namespace.NamespaceContext;
+import javax.xml.xpath.XPath;
+import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathExpressionException;
+import javax.xml.xpath.XPathFactory;
+
+import org.argeo.api.acr.Content;
+import org.argeo.api.acr.ContentNotFoundException;
+import org.argeo.api.acr.spi.ContentProvider;
+import org.argeo.api.acr.spi.ProvidedSession;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+
+public class DomContentProvider implements ContentProvider, NamespaceContext {
+       private Document document;
+
+       // XPath
+       // TODO centralise in some executor?
+       private final ThreadLocal<XPath> xPath;
+
+       public DomContentProvider(Document document) {
+               this.document = document;
+               this.document.normalizeDocument();
+               XPathFactory xPathFactory = XPathFactory.newInstance();
+               xPath = new ThreadLocal<>() {
+
+                       @Override
+                       protected XPath initialValue() {
+                               // TODO set the document as namespace context?
+                               XPath res= xPathFactory.newXPath();
+                               res.setNamespaceContext(DomContentProvider.this);
+                               return res;
+                       }
+               };
+       }
+
+//     @Override
+//     public Content get() {
+//             return new DomContent(this, document.getDocumentElement());
+//     }
+
+//     public Element createElement(String name) {
+//             return document.createElementNS(null, name);
+//
+//     }
+
+       @Override
+       public Content get(ProvidedSession session, String mountPath, String relativePath) {
+               if ("".equals(relativePath))
+                       return new DomContent(session, this, document.getDocumentElement());
+               if (relativePath.startsWith("/"))
+                       throw new IllegalArgumentException("Relative path cannot start with /");
+
+               String xPathExpression = '/' + relativePath;
+               if ("/".equals(mountPath))
+                       xPathExpression = "/cr:root" + xPathExpression;
+               try {
+                       NodeList nodes = (NodeList) xPath.get().evaluate(xPathExpression, document, XPathConstants.NODESET);
+                       if (nodes.getLength() > 1)
+                               throw new IllegalArgumentException(
+                                               "Multiple content found for " + relativePath + " under " + mountPath);
+                       if (nodes.getLength() == 0)
+                               throw new ContentNotFoundException("Path " + relativePath + " under " + mountPath + " was not found");
+                       Element element = (Element) nodes.item(0);
+                       return new DomContent(session, this, element);
+               } catch (XPathExpressionException e) {
+                       throw new IllegalArgumentException("XPath expression " + xPathExpression + " cannot be evaluated", e);
+               }
+       }
+
+       /*
+        * NAMESPACE CONTEXT
+        */
+       @Override
+       public String getNamespaceURI(String prefix) {
+               return document.lookupNamespaceURI(prefix);
+       }
+
+       @Override
+       public String getPrefix(String namespaceURI) {
+               return document.lookupPrefix(namespaceURI);
+       }
+
+       @Override
+       public Iterator<String> getPrefixes(String namespaceURI) {
+               List<String> res = new ArrayList<>();
+               res.add(getPrefix(namespaceURI));
+               return Collections.unmodifiableList(res).iterator();
+       }
+
+}