Xml-db api

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Contents

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XML:DB API with eXist native XML database

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Connecting to the database (and collection)

  • Selecting driver (eXist) 
Class cl = Class.forName("org.exist.xmldb.DatabaseImpl");           
    Database database = (Database)cl.newInstance();
            
    DatabaseManager.registerDatabase(database);
  • Opening a collection 
Collection col = 
        DatabaseManager.getCollection("xmldb:exist://localhost:8080/exist/xmlrpc/db/collection");
  • or (with username and password) 
Collection col = 
        DatabaseManager.getCollection("xmldb:exist://localhost:8080/exist/xmlrpc/db/collection","user", "password");
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Querying

  • Performing XPath or XQuery 
XPathQueryService service =
        (XPathQueryService) col.getService("XPathQueryService", "1.0");
    service.setProperty("indent", "yes");
 
    String query = "for $a in //host[@name='google'] return $a/name";
                    
    ResourceSet result = service.query(query);
  • Viewing results 
ResourceIterator i = result.getIterator();
    while(i.hasMoreResources()) {
        Resource r = i.nextResource();
        System.out.println((String)r.getContent());
    }
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Data modifications 

XPathQueryService service =
        (XPathQueryService) col.getService("XPathQueryService", "1.0");
    service.setProperty("indent", "yes");
  
    String query = "for $a in //host[@id='buttercup'] "
                  +"return update replace $a/name "
                  +"with <name>BuTTerCuP</name>";
                    
    ResourceSet result = service.query(query);
  • by XUpdate 
XUpdateQueryService service = 
        (XUpdateQueryService)col.getService("XUpdateQueryService", "1.0");
    service.setCollection(col);
 
    String xupdate = 
        "<xu:modifications version=\'1.0\' " +
        "        xmlns:xu=\'http://www.xmldb.org/xupdate\'>" +
        "    <xu:insert-after select='//host[1]'>" +
        "       <host id='new'>" +
        "           <name>NewHost</name>" +
        "       </host>" +
        "    </xu:insert-after>" +
        "</xu:modifications>";
            
    service.update(xupdate);
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eXist and XML:DB links

Retrieved from "http://wiki.perfsonar.net/jra1-wiki/index.php/Xml-db_api"
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