package org.korsakow.services.tdg;
import javax.xml.xpath.XPathException;
import javax.xml.xpath.XPathExpressionException;
import org.korsakow.ide.DataRegistry;
import org.korsakow.ide.util.DomUtil;
import org.w3c.dom.Element;
public class PredicateTDG
{
public static final String NODE_NAME = "Predicate";
public static int insert(long object_id, long version, String type) throws XPathException{
return insert(object_id, DataRegistry.getMaxId(), version, type);
}
public static int insert(long object_id, long id, long version, String type) throws XPathExpressionException{
Element tableElement = createPredicateTable(object_id);
Element element = DomUtil.findChildByIdTag(tableElement, NODE_NAME, ""+id);
if (element != null)
return 0;
element = DataRegistry.getDocument().createElement(NODE_NAME);
tableElement.appendChild(element);
DataRegistry.getHelper().setLong(element, "id", id);
DataRegistry.getHelper().setLong(element, "version", version);
return update(id, version, type);
}
public static int update(long id, long version, String type) throws XPathExpressionException{
Element element = DataRegistry.getHelper().findElementByIdTag(id);
if (element == null)
return 0;
DataRegistry.getHelper().setLong(element, "id", id);
DataRegistry.getHelper().setLong(element, "version", version+1);
DataRegistry.getHelper().setString(element, "type", type);
return 1;
}
public static int delete(long id, long version) throws XPathExpressionException {
Element element = DataRegistry.getHelper().findElementByIdTag(id);
if (DomUtil.getLong(element, "version") != version)
return 0;
element.getParentNode().removeChild(element);
return 1;
}
public static int deleteByResource(long resource_id) throws XPathExpressionException {
Element objectElement = DataRegistry.getHelper().findElementByIdTag(resource_id);
if (objectElement == null)
return 0;
Element tableElement = DomUtil.findChildByTagName(objectElement, "predicates");
if (tableElement == null)
return 0;
int count = tableElement.getChildNodes().getLength();
while (tableElement.hasChildNodes())
tableElement.removeChild(tableElement.getFirstChild());
return count;
}
public static Element createPredicateTable(long object_id) throws XPathExpressionException {
Element objectElement = DataRegistry.getHelper().findElementByIdTag(object_id);
Element tableElement = DomUtil.findChildByTagName(objectElement, "predicates");
if (tableElement == null) {
tableElement = DataRegistry.getHelper().appendUniqueElement(objectElement, "predicates");
}
return tableElement;
}
public static void dropTable (long object_id) throws XPathExpressionException{
Element objectElement = DataRegistry.getHelper().findElementByIdTag(object_id);
Element tableElement = DomUtil.findChildByTagName(objectElement, "predicates");
if (tableElement != null)
tableElement.getParentNode().removeChild(tableElement);
}
}