Merged Stefan Pollach's XML Database branch.

src/helma/framework/core/Application.java

@@ -13,7 +13,6 @@ import helma.objectmodel.*;
 import helma.objectmodel.db.*;
 import helma.xmlrpc.*;
 import helma.util.*;
-import com.sleepycat.db.DbException;
 import java.util.*;
 import java.io.*;
 import java.net.URLEncoder;
@@ -231,7 +230,7 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
     /**
      * Get the application ready to run, initializing the evaluators and type manager.
      */
-    public void init () throws DbException, ScriptingException {
+    public void init () throws DatabaseException, ScriptingException {
 	scriptingEngine = new helma.scripting.fesi.FesiScriptingEnvironment ();
 	scriptingEngine.init (this, props);
 
@@ -317,7 +316,7 @@ public class Application extends UnicastRemoteObject implements IRemoteApp, IPat
 	// shut down node manager and embedded db
 	try {
 	    nmgr.shutdown ();
-	} catch (DbException dbx) {
+	} catch (DatabaseException dbx) {
 	    System.err.println ("Error shutting down embedded db: "+dbx);
 	}
 	

src/helma/main/Server.java

@@ -15,7 +15,6 @@ import helma.framework.*;
 import helma.framework.core.*;
 import helma.xmlrpc.*;
 import helma.util.*;
-import com.sleepycat.db.*;
 
 
 /**

src/helma/objectmodel/DatabaseException.java

@@ -0,0 +1,49 @@
+// DatabaseException.java
+ 
+package helma.objectmodel;
+
+
+/**
+ * Thrown on any kind of Database-Error
+ */
+ 
+public class DatabaseException extends RuntimeException {
+
+    public DatabaseException (String msg) {
+	super (msg);
+    }
+
+}
+
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+

src/helma/objectmodel/IDatabase.java

@@ -0,0 +1,35 @@
+// IDatabase.java
+
+package helma.objectmodel;
+
+import helma.objectmodel.db.IDGenerator;
+import helma.objectmodel.INode;
+
+/**
+ * Interface that is implemented by Database wrappers
+ */
+ 
+public interface IDatabase {
+
+	// db-related
+    public void shutdown ();
+
+	// id-related
+	public String      nextID() throws ObjectNotFoundException;
+    public IDGenerator getIDGenerator  (ITransaction transaction) throws Exception;
+	public void        saveIDGenerator (ITransaction transaction, IDGenerator idgen) throws Exception;
+
+	// node-related
+    public INode getNode    (ITransaction transaction, String key) throws Exception;
+    public void  saveNode   (ITransaction transaction, String key, INode node) throws Exception;
+    public void  deleteNode (ITransaction transaction, String key) throws Exception;
+
+	// transaction-related
+    public ITransaction beginTransaction  ();
+    public void         commitTransaction (ITransaction transaction) throws DatabaseException;
+    public void         abortTransaction  (ITransaction transaction) throws DatabaseException;
+
+}
+
+
+

src/helma/objectmodel/ITransaction.java

@@ -0,0 +1,18 @@
+// ITransaction.java
+ 
+package helma.objectmodel;
+
+/**
+  * This interface is kept for databases that are able
+  * to run transactions. Transactions were used for the
+  * Berkeley database and might be used in other future 
+  * databases, so we leave transactions in.
+  */
+
+public interface ITransaction {
+
+}
+
+
+
+

src/helma/objectmodel/db/DbWrapper.java

@@ -1,292 +0,0 @@
-// DbWrapper.java
-// Copyright (c) Hannes Wallnöfer 1999-2000
-
-
-package helma.objectmodel.db;
-
-import com.sleepycat.db.*;
-import helma.objectmodel.ObjectNotFoundException;
-import java.io.*;
-
-/**
- * A wrapper around a Berkeley embedded database. Used to gracefully handle the case
- * when the native library can not be loaded.
- */
-
-public class DbWrapper {
-
-    private boolean loaded, useTransactions;
-
-    private Db db;
-    DbEnv dbenv;
-    final int checkpointPause = 600000;  // min. 10 minutes between checkpoints
-    volatile long lastCheckpoint = 0;
-    volatile long txncount=0;
-
-    private File dbBaseDir;
-    private NodeManager nmgr;
-    private String dbHome;
-
-    public DbWrapper (String dbHome, String dbFilename, NodeManager nmgr, boolean useTx) throws DbException {
-
-	this.dbHome = dbHome;
-	this.nmgr = nmgr;
-
-	try {
-	    dbBaseDir = new File (dbHome);
-	    if (!dbBaseDir.exists())
-	        dbBaseDir.mkdirs();
-
-	    useTransactions = useTx;
-
-	    int dbInitFlags = Db.DB_CREATE | Db.DB_THREAD | Db.DB_INIT_MPOOL;
-	    if (useTransactions) {
-	        dbInitFlags = dbInitFlags | Db.DB_INIT_TXN;
-	    }
-
-	    dbenv = new DbEnv (0);
-	    try {
-	        dbenv.open (dbHome, dbInitFlags, 0); // for berkeley 3.0, add second parameter (null)
-	    } catch (FileNotFoundException fnf) {
-	        // we just created the dirs, so this shouldn't happen
-	    }
-
-	    try {
-	        dbenv.set_error_stream(System.err);
-	        dbenv.set_errpfx("Sleepycat");
-	    } catch (Exception e) {
-	        System.err.println("Error in DbWrapper: "+e.toString());
-	    }
-
-	    db = new Db (dbenv, 0);
-	    try {
-	        db.upgrade  (dbFilename, 0);
-	    } catch (Exception ignore) {
-	        // nothing to upgrade, db doesn't exist
-	    }
-
-	    try {
-	        db.open (dbFilename, null, Db.DB_BTREE, Db.DB_CREATE, 0644);
-	    } catch (FileNotFoundException fnf) {
-	        // we just created the dirs, so this shouldn't happen
-	    }
-	    loaded = true;
-
-	} catch (NoClassDefFoundError noclass) {
-	    nmgr.app.logEvent ("Warning: Using internal file based db as fallback.");
-	    nmgr.app.logEvent ("Reason: "+noclass);
-	    loaded = false;
-	} catch (UnsatisfiedLinkError nolib) {
-	    nmgr.app.logEvent ("Warning: Using internal file based db as fallback.");
-	    nmgr.app.logEvent ("Reason: "+nolib);
-	    loaded = false;
-	}
-	
-    }
-
-
-    public void shutdown () throws DbException {
-	if (loaded) {
-	    db.close (0);
-	    // closing the dbenv leads to segfault when app is restarted
-	    // dbenv.close (0);
-	    // dbenv.remove (dbHome, Db.DB_FORCE);
-	    nmgr.app.logEvent ("Closed Berkeley DB");
-	}
-    }
-
-    public DbTxn beginTransaction () throws DbException {
-	if (loaded && useTransactions)
-	    return dbenv.txn_begin (null, 0);
-	else
-	    return null;
-    }
-
-    public void commitTransaction (DbTxn txn) throws DbException  {
-	if (txn == null || !loaded || !useTransactions)
-	    return;
-	txn.commit (0);
-             if (++txncount%100 == 0 && System.currentTimeMillis()-checkpointPause > lastCheckpoint) {
-	    // checkpoint transaction logs in time interval specified by server.checkpointPause
-	    // if there are more then 100 transactions to checkpoint.
-	    checkpoint ();
-	}
-    }
-
-    public void abortTransaction (DbTxn txn) throws DbException {
-	if (txn == null || !loaded || !useTransactions)
-	    return;
-	txn.abort ();
-    }
-
-    protected void checkpoint () throws DbException {
-	if (!loaded || !useTransactions || txncount == 0)
-	    return;
-	long now = System.currentTimeMillis();
-	if (now - lastCheckpoint < checkpointPause)
-	    return;
-	dbenv.txn_checkpoint (0, 0, 0); // for berkeley 3.0, remove third 0 parameter
-	txncount = 0;
-	lastCheckpoint = now;
-	nmgr.app.logEvent ("Spent "+(System.currentTimeMillis()-now)+" in checkpoint");
-    }
-
-    public IDGenerator getIDGenerator (DbTxn txn, String kstr) throws Exception {
-	if (loaded)
-	    return getIDGenFromDB (txn, kstr);
-	else
-	    return getIDGenFromFile (kstr);
-    }
-
-    public Node getNode (DbTxn txn, String kstr) throws Exception {
-	if (loaded)
-	    return getNodeFromDB (txn, kstr);
-	else
-	    return getNodeFromFile (kstr);
-    }
-
-    public void save (DbTxn txn, String kstr, Object obj) throws Exception {
-	if (loaded)
-	    saveToDB (txn, kstr, obj);
-	else
-	    saveToFile (kstr, obj);
-    }
-
-    public void delete (DbTxn txn, String kstr) throws Exception {
-	if (loaded)
-	    deleteFromDB (txn, kstr);
-	else
-	    deleteFromFile (kstr);
-    }
-
-
-    private IDGenerator getIDGenFromDB (DbTxn txn, String kstr) throws Exception {
-	long now = System.currentTimeMillis ();
-	byte[] kbuf = kstr.getBytes ();
-	Dbt key = new Dbt (kbuf);
-	key.set_size (kbuf.length);
-	Dbt data = new Dbt ();
-	data.set_flags (Db.DB_DBT_MALLOC);
-	
-	db.get (txn, key, data, 0);
-
-	byte[] b = data.get_data ();
-	if (b == null)
-	    throw new ObjectNotFoundException ("Object not found for key "+kstr+".");
-
-	IDGenerator idgen = null;
-	ByteArrayInputStream bin = new ByteArrayInputStream (b);
-	ObjectInputStream oin = new ObjectInputStream (bin);
-	idgen = (IDGenerator) oin.readObject ();
-
-	oin.close ();
-	return idgen;
-    }
-
-
-    private Node getNodeFromDB (DbTxn txn, String kstr) throws Exception {
-	long now = System.currentTimeMillis ();
-	byte[] kbuf = kstr.getBytes ();
-	Dbt key = new Dbt (kbuf);
-	key.set_size (kbuf.length);
-	Dbt data = new Dbt ();
-	data.set_flags (Db.DB_DBT_MALLOC);
-	
-	db.get (txn, key, data, 0);
-
-	byte[] b = data.get_data ();
-	if (b == null)
-	    throw new ObjectNotFoundException ("Object not found for key "+kstr+".");
-
-	Node node = null;
-	ByteArrayInputStream bin = new ByteArrayInputStream (b);
-	ObjectInputStream oin = new ObjectInputStream (bin);
-	node = (Node) oin.readObject ();
-	oin.close ();
-	return node;
-    }
-
-
-    private void saveToDB (DbTxn txn, String kstr, Object obj) throws Exception {
-	long now = System.currentTimeMillis ();
-	byte kbuf[] = kstr.getBytes();
-	ByteArrayOutputStream bout = new  ByteArrayOutputStream ();
-	ObjectOutputStream oout = new ObjectOutputStream (bout);
-	oout.writeObject (obj);
-	oout.close ();
-	byte vbuf[] = bout.toByteArray ();
-
-	Dbt key = new Dbt (kbuf);
-	key.set_size (kbuf.length);
-	Dbt value = new Dbt (vbuf);
-	value.set_size (vbuf.length);
-	
-	db.put (txn, key, value, 0);
-	// nmgr.app.logEvent ("saved "+obj+", size = "+vbuf.length);
-    }
-
-    private void deleteFromDB (DbTxn txn, String kstr) throws Exception {
-
-	byte kbuf[] = kstr.getBytes();
-
-	Dbt key = new Dbt (kbuf);
-	key.set_size (kbuf.length);
-	
-	db.del (txn, key, 0);
-    }
-
-    ////////////////////////////////////////////////////////////////////////////////
-    // File based fallback methods
-    ///////////////////////////////////////////////////////////////////////////////
-
-    private IDGenerator getIDGenFromFile (String kstr) throws Exception {
-
-	File f = new File (dbBaseDir, kstr);
-
-	if ( ! f.exists() )
-	    throw new ObjectNotFoundException ("Object not found for key "+kstr+".");
-
-	IDGenerator idgen = null;
-	FileInputStream bin = new FileInputStream (f);
-	ObjectInputStream oin = new ObjectInputStream (bin);
-	idgen = (IDGenerator) oin.readObject ();
-
-	oin.close ();
-	return idgen;
-    }
-
-
-    private Node getNodeFromFile (String kstr) throws Exception {
-
-	File f = new File (dbBaseDir, kstr);
-
-	if ( ! f.exists() )
-	    throw new ObjectNotFoundException ("Object not found for key "+kstr+".");
-
-	Node node = null;
-	FileInputStream bin = new FileInputStream (f);
-	ObjectInputStream oin = new ObjectInputStream (bin);
-	node = (Node) oin.readObject ();
-	oin.close ();
-	return node;
-    }
-
-
-    private void saveToFile (String kstr, Object obj) throws Exception {
-
-	File f = new File (dbBaseDir, kstr);
-
-	FileOutputStream bout = new  FileOutputStream (f);
-	ObjectOutputStream oout = new ObjectOutputStream (bout);
-	oout.writeObject (obj);
-	oout.close ();
-    }
-
-    private void deleteFromFile (String kstr) throws Exception {
-
-	File f = new File (dbBaseDir, kstr);
-	f.delete();
-    }
-
-
-}

src/helma/objectmodel/db/IDGenerator.java

@@ -58,7 +58,7 @@ public final class IDGenerator implements Serializable {
     /**
      * Get the current counter  value
      */
-    protected long getValue () {
+    public long getValue () {
 	return counter;
     }
 

src/helma/objectmodel/db/Node.java

@@ -124,6 +124,20 @@ public final class Node implements INode, Serializable {
 	out.writeObject (prototype);
     }
 
+    /**
+     * used by Xml deserialization
+     */
+     public void setPropMap (Hashtable propMap)	{
+	this.propMap = propMap;
+     }
+
+    /**
+     * used by Xml deserialization
+     */
+     public void setSubnodes (List subnodes)	{
+	this.subnodes = subnodes;
+}
+
     private transient String prototype;
 
     private transient NodeHandle handle;
@@ -164,8 +178,9 @@ public final class Node implements INode, Serializable {
     /**
      * Creates a new Node with the given name. Only used by NodeManager for "root nodes" and
      * not in a Transaction context, which is why we can immediately mark it as CLEAN.
+     * ADD: used by wrapped database to re-create an existing Node.
      */
-    protected Node (String name, String id, String prototype, WrappedNodeManager nmgr) {
+    public Node (String name, String id, String prototype, WrappedNodeManager nmgr) {
 	this.nmgr = nmgr;
  	this.id = id;
 	this.name = name == null || "".equals (name) ? id : name;
@@ -176,6 +191,17 @@ public final class Node implements INode, Serializable {
     }
 
 
+    /**
+     * Constructor used to create a Node with a given name from a wrapped database.
+     */
+    public Node (String name, String id, String prototype, WrappedNodeManager nmgr, long created, long lastmodified)	{
+	this (name,id,prototype,nmgr);
+	this.created = created;
+	this.lastmodified = lastmodified;
+    }
+
+
+
     /**
      * Constructor used for virtual nodes.
      */
@@ -459,6 +485,8 @@ public final class Node implements INode, Serializable {
 	            } else {
 	                anonymous = true;
 	            }
+	        } else if (p.contains (this) > -1) {
+	           anonymous = true;
 	        }
 	    } catch (Exception ignore) {
 	        // just fall back to default method
@@ -577,6 +605,10 @@ public final class Node implements INode, Serializable {
 	parentHandle = parent == null ? null : parent.getHandle ();
     }
 
+    public void setParentHandle (NodeHandle parent)	{
+	parentHandle = parent;
+    }
+
     /**
      * This version of setParent additionally marks the node as anonymous or non-anonymous,
      * depending on the string argument. This is the version called from the scripting framework,
@@ -1197,6 +1229,10 @@ public final class Node implements INode, Serializable {
 	return new Enum ();
     }
 
+    public List getSubnodeList() {
+	return subnodes;
+    }
+
     private boolean ignoreSubnodeChange () {
 	// return true if a change in subnodes can be ignored because it is
 	// stored in the subnodes themselves.
@@ -1233,7 +1269,9 @@ public final class Node implements INode, Serializable {
 	// return propMap == null ? new Vector ().elements () : propMap.elements ();
     }
 
-
+    public Hashtable getPropMap()	{
+	return propMap;
+    }
 
     public IProperty get (String propname, boolean inherit) {
 	return getProperty (propname, inherit);

src/helma/objectmodel/db/NodeManager.java

@@ -6,7 +6,6 @@ package helma.objectmodel.db;
 import helma.util.CacheMap;
 import helma.objectmodel.*;
 import helma.framework.core.Application;
-import com.sleepycat.db.*;
 import java.sql.*;
 import java.io.*;
 import java.util.*;
@@ -26,7 +25,7 @@ public final class NodeManager {
 
     private Replicator replicator;
 
-    protected DbWrapper db;
+    protected IDatabase db;
 
     protected IDGenerator idgen;
 
@@ -42,7 +41,7 @@ public final class NodeManager {
     *  Create a new NodeManager for Application app. An embedded database will be
     * created in dbHome if one doesn't already exist.
     */
-    public NodeManager (Application app, String dbHome, Properties props) throws DbException {
+    public NodeManager (Application app, String dbHome, Properties props) throws DatabaseException {
 	this.app = app;
 	int cacheSize = Integer.parseInt (props.getProperty ("cachesize", "1000"));
 	// Make actual cache size bigger, since we use it only up to the threshold
@@ -68,7 +67,7 @@ public final class NodeManager {
 	    idBaseValue = Math.max (1l, idBaseValue); // 0 and 1 are reserved for root nodes
 	} catch (NumberFormatException ignore) {}
 
-	db = new DbWrapper (dbHome, helma.main.Server.dbFilename, this, helma.main.Server.useTransactions);
+	db = new XmlDatabase (dbHome, helma.main.Server.dbFilename, this);
 	initDb ();
 
 	logSql = "true".equalsIgnoreCase(props.getProperty ("logsql"));
@@ -77,44 +76,44 @@ public final class NodeManager {
    /**
     * Method used to create the root node and id-generator, if they don't exist already.
     */
-    public void initDb () throws DbException {
+    public void initDb () throws DatabaseException {
 
-	DbTxn txn = null;
+	ITransaction txn = null;
 	try {
 	    txn = db.beginTransaction ();
 
 	    try {
-	        idgen = db.getIDGenerator (txn, "idgen");
+	        idgen = db.getIDGenerator (txn);
 	        if (idgen.getValue() < idBaseValue) {
 	            idgen.setValue (idBaseValue);
-	            db.save (txn, "idgen", idgen);
+	            db.saveIDGenerator (txn, idgen);
 	        }
 	    } catch (ObjectNotFoundException notfound) {
 	        // will start with idBaseValue+1
 	        idgen = new IDGenerator (idBaseValue);
-	        db.save (txn, "idgen", idgen);
+	        db.saveIDGenerator (txn, idgen);
 	    }
 
 	    // check if we need to set the id generator to a base value
 	
 	    Node node = null;
 	    try {
-	        node = db.getNode (txn, "0");
+	        node = (Node)db.getNode (txn, "0");
 	        node.nmgr = safe;
 	    } catch (ObjectNotFoundException notfound) {
 	        node = new Node ("root", "0", "root", safe);
 	        node.setDbMapping (app.getDbMapping ("root"));
-	        db.save (txn, node.getID (), node);
+	        db.saveNode (txn, node.getID (), node);
 	        registerNode (node); // register node with nodemanager cache
 	    }
 
 	    try {
-	        node = db.getNode (txn, "1");
+	        node = (Node)db.getNode (txn, "1");
 	        node.nmgr = safe;
 	    } catch (ObjectNotFoundException notfound) {
 	        node = new Node ("users", "1", null, safe);
 	        node.setDbMapping (app.getDbMapping ("__userroot__"));
-	        db.save (txn, node.getID (), node);
+	        db.saveNode (txn, node.getID (), node);
 	        registerNode (node); // register node with nodemanager cache
 	    }
 
@@ -125,7 +124,7 @@ public final class NodeManager {
 	    try {
 	        db.abortTransaction (txn);
 	    } catch (Exception ignore) {}
-	    throw (new DbException ("Error initializing db"));
+	    throw (new DatabaseException ("Error initializing db"));
 	}
     }
 
@@ -134,7 +133,7 @@ public final class NodeManager {
     *  Shut down this node manager. This is called when the application using this
     *  node manager is stopped.
     */
-    public void shutdown () throws DbException {
+    public void shutdown () throws DatabaseException {
 	db.shutdown ();
 	if (cache != null) {
 	    synchronized (cache) {
@@ -360,7 +359,7 @@ public final class NodeManager {
     *  Insert a new node in the embedded database or a relational database table, depending
     * on its db mapping.
     */
-    public void insertNode (DbWrapper db, DbTxn txn, Node node) throws Exception {
+    public void insertNode (IDatabase db, ITransaction txn, Node node) throws Exception {
 
 	Transactor tx = (Transactor) Thread.currentThread ();
 	// tx.timer.beginEvent ("insertNode "+node);
@@ -368,7 +367,7 @@ public final class NodeManager {
 	DbMapping dbm = node.getDbMapping ();
 
 	if (dbm == null || !dbm.isRelational ()) {
-	    db.save (txn, node.getID (), node);
+	    db.saveNode (txn, node.getID (), node);
 	} else {
 	    app.logEvent ("inserting relational node: "+node.getID ());
 	    TableDataSet tds = null;
@@ -438,7 +437,7 @@ public final class NodeManager {
     *  Updates a modified node in the embedded db or an external relational database, depending
     * on its database mapping.
     */
-    public void updateNode (DbWrapper db, DbTxn txn, Node node) throws Exception {
+    public void updateNode (IDatabase db, ITransaction txn, Node node) throws Exception {
 
 	Transactor tx = (Transactor) Thread.currentThread ();
 	// tx.timer.beginEvent ("updateNode "+node);
@@ -446,7 +445,7 @@ public final class NodeManager {
 	DbMapping dbm = node.getDbMapping ();
 
 	if (dbm == null || !dbm.isRelational ()) {
-	    db.save (txn, node.getID (), node);
+	    db.saveNode (txn, node.getID (), node);
 	} else {
 
 	    TableDataSet tds = null;
@@ -537,7 +536,7 @@ public final class NodeManager {
     /**
     *  Performs the actual deletion of a node from either the embedded or an external SQL database.
     */
-    public void deleteNode (DbWrapper db, DbTxn txn, Node node) throws Exception {
+    public void deleteNode (IDatabase db, ITransaction txn, Node node) throws Exception {
 
 	Transactor tx = (Transactor) Thread.currentThread ();
 	// tx.timer.beginEvent ("deleteNode "+node);
@@ -545,7 +544,7 @@ public final class NodeManager {
 	DbMapping dbm = node.getDbMapping ();
 
 	if (dbm == null || !dbm.isRelational ()) {
-	    db.delete (txn, node.getID ());
+	    db.deleteNode (txn, node.getID ());
 	} else {
 	    Statement st = null;
 	    try {
@@ -865,14 +864,14 @@ public final class NodeManager {
     // private getNode methods
     ///////////////////////////////////////////////////////////////////////////////////////
 
-    private Node getNodeByKey (DbTxn txn, DbKey key) throws Exception {
+    private Node getNodeByKey (ITransaction txn, DbKey key) throws Exception {
 	// Note: Key must be a DbKey, otherwise will not work for relational objects
 	Node node = null;
 	DbMapping dbm = app.getDbMapping (key.getStorageName ());
 	String kstr = key.getID ();
 	
 	if (dbm == null || !dbm.isRelational ()) {
-	    node = db.getNode (txn, kstr);
+	    node = (Node)db.getNode (txn, kstr);
 	    node.nmgr = safe;
 	    if (node != null && dbm != null)
 	        node.setDbMapping (dbm);
@@ -905,7 +904,7 @@ public final class NodeManager {
 	return node;
     }
 
-    private Node getNodeByRelation (DbTxn txn, Node home, String kstr, Relation rel) throws Exception {
+    private Node getNodeByRelation (ITransaction txn, Node home, String kstr, Relation rel) throws Exception {
 	Node node = null;
 
 	if (rel.virtual) {
@@ -922,13 +921,13 @@ public final class NodeManager {
 	} else if (rel != null && rel.groupby != null) {
 	    node = home.getGroupbySubnode (kstr, false);
 	    if (node == null && (rel.otherType == null || !rel.otherType.isRelational ())) {
-	        node = db.getNode (txn, kstr);
+	        node = (Node)db.getNode (txn, kstr);
 	        node.nmgr = safe;
 	    }
 	    return node;
 
 	} else if (rel == null || rel.otherType == null || !rel.otherType.isRelational ()) {
-	    node = db.getNode (txn, kstr);
+	    node = (Node)db.getNode (txn, kstr);
 	    node.nmgr = safe;
 	    node.setDbMapping (rel.otherType);
 	    return node;

src/helma/objectmodel/db/Property.java

@@ -210,6 +210,17 @@ public final class Property implements IProperty, Serializable, Cloneable {
 	dirty = true;
     }
 
+    public void setNodeHandle (NodeHandle value) {
+	if (type == NODE)
+	    unregisterNode ();
+	if (type == JAVAOBJECT)
+	    this.jvalue = null;
+	// registerNode (value);
+	type = NODE;
+	nhandle = value;
+	dirty = true;
+    }
+
     public void setJavaObjectValue (Object value) {
 	if (type == NODE)
 	    unregisterNode ();

src/helma/objectmodel/db/Transactor.java

@@ -9,7 +9,6 @@ import java.sql.*;
 import helma.objectmodel.*;
 import helma.util.Timer;
 import helma.framework.TimeoutException;
-import com.sleepycat.db.*;
 
 /**
  * A subclass of thread that keeps track of changed nodes and triggers 
@@ -30,7 +29,7 @@ public class Transactor extends Thread {
     private volatile boolean killed;
 
     // Transaction for the embedded database
-    protected DbTxn txn;
+    protected ITransaction txn;
     // Transactions for SQL data sources
     protected HashMap sqlCon;
 
@@ -108,7 +107,7 @@ public class Transactor extends Thread {
     public synchronized void begin (String tnm) throws Exception {
 
 	if (killed)
-	    throw new DbException ("Transaction started on killed thread");
+	    throw new DatabaseException ("Transaction started on killed thread");
 
 	if (active)
 	    abort ();
@@ -171,7 +170,7 @@ public class Transactor extends Thread {
 	cleannodes.clear ();
 
 	if (nmgr.idgen.dirty) {
-	    nmgr.db.save (txn, "idgen", nmgr.idgen);
+	    nmgr.db.saveIDGenerator (txn, nmgr.idgen);
 	    nmgr.idgen.dirty = false;
 	}
 

src/helma/objectmodel/db/XmlDatabase.java

@@ -0,0 +1,95 @@
+package helma.objectmodel.db;
+
+import java.io.*;
+import java.util.Date;
+import org.w3c.dom.Element;
+import org.w3c.dom.Document;
+
+import helma.objectmodel.*;
+import helma.objectmodel.dom.*;
+
+/**
+ * A simple XML-database
+ */
+
+public class XmlDatabase implements IDatabase {
+
+	private String dbHome;
+	private File dbBaseDir;
+	private NodeManager nmgr;
+	private IDGenerator idgen;
+	// character encoding to use when writing files.
+	// use standard encoding by default.
+	private String encoding = null;
+
+	public XmlDatabase (String dbHome, String dbFilename, NodeManager nmgr) throws DatabaseException {
+		this.dbHome = dbHome;
+		this.nmgr = nmgr;
+		dbBaseDir = new File (dbHome);
+		if (!dbBaseDir.exists() && !dbBaseDir.mkdirs() )
+			throw new RuntimeException("Couldn't create DB-directory");
+	}
+
+	public void shutdown ()	 {   }
+	public ITransaction beginTransaction () throws DatabaseException {    return null;    }
+	public void commitTransaction (ITransaction txn) throws DatabaseException {    }
+	public void abortTransaction (ITransaction txn) throws DatabaseException {    }
+
+	public String nextID() throws ObjectNotFoundException {
+		if (idgen==null) {
+			getIDGenerator(null);
+		}
+		return idgen.newID();
+	}
+
+	public IDGenerator getIDGenerator (ITransaction txn) throws ObjectNotFoundException {
+		File file = new File (dbBaseDir, "idgen.xml");
+		this.idgen = IDGenParser.getIDGenerator(file);
+		return idgen;
+	}
+
+	public void saveIDGenerator (ITransaction txn, IDGenerator idgen) throws Exception {
+		File file = new File (dbBaseDir, "idgen.xml");
+		IDGenParser.saveIDGenerator(idgen,file);
+		this.idgen = idgen;
+	}
+
+	public INode getNode (ITransaction txn, String kstr) throws Exception {
+		File f = new File (dbBaseDir, kstr+".xml");
+		if ( ! f.exists() )
+			throw new ObjectNotFoundException ("Object not found for key "+kstr+".");
+		try {
+			XmlReader reader = new XmlReader (nmgr);
+			Node node = (Node)reader.read (f, null);
+			return node;
+		} catch ( RuntimeException x )   {
+			nmgr.app.logEvent("error reading node from XmlDatbase: " + x.toString() );
+			throw new ObjectNotFoundException(x.toString());
+		}
+	}
+
+	public void saveNode (ITransaction txn, String kstr, INode node) throws Exception {
+		XmlWriter writer = null;
+		File file = new File (dbBaseDir,kstr+".xml");
+		if (encoding != null)
+		    writer = new XmlWriter (file, encoding);
+		else
+		    writer = new XmlWriter (file);
+		writer.setMaxLevels(1);
+		boolean result = writer.write((Node)node);
+		writer.close();
+	}
+
+	public void deleteNode (ITransaction txn, String kstr) throws Exception {
+		File f = new File (dbBaseDir, kstr+".xml");
+		f.delete();
+	}
+
+	public void setEncoding (String enc) {
+		this.encoding = encoding;
+	}
+
+	public String getEncoding () {
+		return encoding;
+	}
+}

src/helma/objectmodel/dom/IDGenParser.java

@@ -0,0 +1,37 @@
+package helma.objectmodel.dom;
+
+import java.io.*;
+import java.util.Date;
+import org.w3c.dom.*;
+
+import helma.objectmodel.ObjectNotFoundException;
+import helma.objectmodel.db.IDGenerator;
+
+public class IDGenParser	{
+
+    public static IDGenerator getIDGenerator (File file) throws ObjectNotFoundException	{
+		if ( ! file.exists() )
+		    throw new ObjectNotFoundException ("IDGenerator not found in idgen.xml");
+		try	{
+			Document document = XmlUtil.parse(new FileInputStream (file));
+			org.w3c.dom.Element tmp = (Element)document.getDocumentElement().getElementsByTagName("counter").item(0);
+			return new IDGenerator( Long.parseLong (XmlUtil.getTextContent(tmp)) );
+		}	catch (Exception e)		{
+			throw new ObjectNotFoundException(e.toString());
+		}
+    }
+
+	public static IDGenerator saveIDGenerator (IDGenerator idgen, File file) throws Exception	{
+		OutputStreamWriter out = new OutputStreamWriter (new  FileOutputStream (file));
+		out.write ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
+		out.write ("<!-- printed by helma object publisher     -->\n");
+		out.write ("<!-- created " + (new Date()).toString() + " -->\n" );
+		out.write ("<xmlroot>\n");
+		out.write ("  <counter>" + idgen.getValue() + "</counter>\n");
+		out.write ("</xmlroot>\n");
+		out.close (); 
+		return idgen;
+	}
+	
+}
+

src/helma/objectmodel/dom/XmlConstants.java

@@ -2,7 +2,7 @@ package helma.objectmodel.dom;
 
 public interface XmlConstants	{
 	
-	public final String NAMESPACE = "http://www.helma.org/";
+	public final String NAMESPACE = "http://www.helma.org/docs/guide/features/database";
 	public final String DATEFORMAT = "dd.MM.yyyy HH:mm:ss z";
 
 }

src/helma/objectmodel/dom/XmlConverter.java

@@ -108,6 +108,8 @@ public class XmlConverter implements XmlConstants	{
 				continue;
 			}
 
+			// FIXME: handle CDATA!
+
 			// it's some kind of element (property or child)
 			if ( childNode.getNodeType()==org.w3c.dom.Node.ELEMENT_NODE )	{
 

src/helma/objectmodel/dom/XmlReader.java

@@ -1,91 +1,95 @@
 package helma.objectmodel.dom;
 
-import java.io.*;
+import java.io.File;
-import java.net.*;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.InputStream;
+
 import java.text.SimpleDateFormat;
 import java.text.ParseException;
-import java.util.*;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Hashtable;
+import java.util.List;
 
-import javax.xml.parsers.*;
 import org.w3c.dom.*;
 
-import helma.objectmodel.*;
+import helma.objectmodel.INode;
+import helma.objectmodel.db.DbKey;
+import helma.objectmodel.db.ExternalizableVector;
+import helma.objectmodel.db.Node;
+import helma.objectmodel.db.NodeHandle;
+import helma.objectmodel.db.NodeManager;
+import helma.objectmodel.db.Property;
 
 public class XmlReader implements XmlConstants	{
 
-	private int offset = 0;
 	private HashMap convertedNodes;
+	private NodeManager nmgr = null;
 
-	public XmlReader()	{
+	public XmlReader ()	{
 	}
 	
-	public INode read( String desc )	{
+	public XmlReader (NodeManager nmgr)	{
-		return read(desc, new TransientNode() );
+		this.nmgr = nmgr;
 	}
 
-	public INode read( String desc, INode helmaNode ) throws RuntimeException	{
+	/**
+	  * main entry to read an xml-file.
+	  */
+	public INode read (File file, INode helmaNode) throws RuntimeException	{
 		try	{
-			return read( new File(desc), helmaNode );
+			return read (new FileInputStream(file), helmaNode);
-		}	catch ( FileNotFoundException notfound )	{
+		}	catch (FileNotFoundException notfound)	{
-			throw new RuntimeException( "couldn't find xml-file: " + desc );
+			System.err.println ("couldn't find xml-file: " + file.getAbsolutePath ());
-		}	catch ( IOException ioerror )	{
-			throw new RuntimeException( "couldn't read xml: " + desc );
-		}
-	}
-
-	public INode read( File file, INode helmaNode ) throws RuntimeException, FileNotFoundException	{
-		return read( new FileInputStream(file), helmaNode );
-	}
-
-	public INode read( InputStream in, INode helmaNode ) throws RuntimeException	{
-		Document document = XmlUtil.parse(in);
-		if ( document!=null && document.getDocumentElement()!=null )	{
-			Node tmp = document.getDocumentElement().getFirstChild();
-			Element workelement = null;
-			while( tmp!=null )	{
-				tmp = tmp.getNextSibling();
-				if ( tmp.getNodeType()==Node.ELEMENT_NODE )	{
-					workelement = (Element) tmp;
-					break;
-				}
-			}
-			return startConversion( helmaNode, workelement );
-		}	else	{
 			return helmaNode;
 		}
 	}
 
-	public INode startConversion( INode helmaNode, Element element )	{
+	/**
-		convertedNodes = new HashMap();
+	  * read an InputStream with xml-content.
-		INode convertedNode = convert(helmaNode, element );
+	  */
+	public INode read (InputStream in, INode helmaNode) throws RuntimeException	{
+		if (helmaNode==null && nmgr==null)
+			throw new RuntimeException ("can't create a new Node without a NodeManager");
+		Document document = XmlUtil.parse (in);
+		Element element = XmlUtil.getFirstElement(document);
+		if (element==null)
+			throw new RuntimeException ("corrupted xml-file");
+
+		if (helmaNode==null)	{
+			return convert (element);
+		}	else	{
+			convertedNodes = new HashMap ();
+			INode convertedNode = convert (element, helmaNode);
 			convertedNodes = null;
 			return convertedNode;
 		}
+	}
 
-	public INode convert( INode helmaNode, Element element )	{
+	/**
-		offset++;
+	  * convert children of an Element to a given helmaNode
-		String idref = element.getAttributeNS(NAMESPACE, "idref");
+	  */
-		String key = idref + "-" + element.getAttributeNS(NAMESPACE, "prototyperef");
+	public INode convert (Element element, INode helmaNode)	{
+		String idref = element.getAttribute("idref");
+		String key = idref + "-" + element.getAttribute("prototyperef");
 		if( idref!=null && !idref.equals("") )	{
 			if( convertedNodes.containsKey(key) )	{
-				offset--;
 				return (INode)convertedNodes.get(key);
 			}
 		}
-		key = element.getAttributeNS(NAMESPACE, "id") + "-" + element.getAttributeNS(NAMESPACE, "prototype");
+		key = element.getAttribute("id") + "-" + element.getAttribute("prototype");
 		convertedNodes.put( key, helmaNode );
-
+		String prototype = element.getAttribute("prototype");
-		// FIXME: import id on persistent nodes
-		String prototype = element.getAttributeNS(NAMESPACE, "prototype");
 		if( !prototype.equals("") && !prototype.equals("hopobject") )	{
 			helmaNode.setPrototype( prototype );
 		}
 		children(helmaNode, element);
-		offset--;
 		return helmaNode;
 	}
 
 
+	// used by convert(Element,INode)
 	private INode children( INode helmaNode, Element element )	{
 		NodeList list = element.getChildNodes();
 		int len = list.getLength();
@@ -94,16 +98,23 @@ public class XmlReader implements XmlConstants	{
 			try	{
 				childElement = (Element)list.item(i);
 			}	catch( ClassCastException e )	{
-				continue;
+				continue;		// ignore CDATA, comments etc
 			}
 			INode workNode = null;
+
 			if ( childElement.getTagName().equals("hop:child") )	{
-				convert( helmaNode.createNode(null), childElement );
+
-			}	else if ( !"".equals(childElement.getAttributeNS(NAMESPACE,"id")) || !"".equals(childElement.getAttributeNS(NAMESPACE,"idref")) )	{
+				convert (childElement, helmaNode.createNode(null));
-				// we've got an object!
+
-				helmaNode.setNode( childElement.getTagName(), convert( helmaNode.createNode(childElement.getTagName()), childElement ) );
+			}	else if ( !"".equals(childElement.getAttribute("id")) || !"".equals(childElement.getAttribute("idref")) )	{
+
+				String childTagName = childElement.getTagName();
+				INode newNode = convert (childElement, helmaNode.createNode (childTagName));
+				helmaNode.setNode (childTagName, newNode);
+
 			}	else	{
-				String type = childElement.getAttribute("hop:type");
+
+				String type = childElement.getAttribute("type");
 				String key  = childElement.getTagName();
 				String content = XmlUtil.getTextContent(childElement);
 				if ( type.equals("boolean") )	{
@@ -132,26 +143,101 @@ public class XmlReader implements XmlConstants	{
 		return helmaNode;
 	}
 
-	/** for testing */
+
-	public static void main ( String args[] ) throws Exception	{
+	/**
+	  * This is a basic de-serialization method for XML-2-Node conversion.
+	  * It reads a Node from a database-like file and should return a Node
+	  * that matches exactly the one dumped to that file before.
+	  * It only supports persistent-capable Nodes (from objectmodel.db-package).
+	  */
+	public helma.objectmodel.db.Node convert (Element element)	{
+		// FIXME: this method should use Element.getAttributeNS():
+		// FIXME: do we need the name value or is it retrieved through mappings anyway?
+		String name = element.getAttribute("name");
+// 		String name = null;
+		String id = element.getAttribute("id");
+		String prototype = element.getAttribute("prototype");
+		if ( "".equals(prototype) )
+			prototype = "hopobject";
+		helma.objectmodel.db.Node helmaNode = null;
 		try		{
-			XmlReader x = new XmlReader ();
+			long created = Long.parseLong (element.getAttribute	("created"));
-			INode node = x.read("test.xml");
+			long lastmodified = Long.parseLong (element.getAttribute	("lastModified"));
-		}	catch ( Exception e )	{
+			helmaNode = new helma.objectmodel.db.Node (name,id,prototype,nmgr.safe,created,lastmodified);
-				System.out.println("exception " + e.toString() );
+		}	catch ( NumberFormatException e )	{
-			throw new RuntimeException(e.toString());
+			helmaNode = new helma.objectmodel.db.Node (name,id,prototype,nmgr.safe);
-		}
 		}
 
+		// now loop through all child elements and retrieve properties/subnodes for this node.
+		NodeList list = element.getChildNodes();
+		int len = list.getLength();
+		Hashtable propMap  = new Hashtable();
+		List      subnodes = new ExternalizableVector();
+		for ( int i=0; i<len; i++ )	{
 
-	/** for testing */
+			Element childElement;
-	void debug(Object msg)	{
+			try	{
-		for ( int i=0; i<offset; i++ )	{
+				childElement = (Element)list.item(i);
-			System.out.print("   ");
+			}	catch( ClassCastException e )	{
-		}
+				continue;		// ignore CDATA, comments etc
-		System.out.println(msg.toString());
 			}
 
+			if ( childElement.getTagName().equals("hop:child") )	{
+				// add a new NodeHandle, presume all IDs in this objectcache are unique,
+				// a prerequisite for a simple internal database.
+				subnodes.add (new NodeHandle (new DbKey(null,childElement.getAttribute("idref") ) ) );
+				continue;
+			}
+
+			if ( childElement.getTagName().equals("hop:parent") )	{
+				// add a NodeHandle to parent object
+				helmaNode.setParentHandle (new NodeHandle (new DbKey(null,childElement.getAttribute("idref") ) ) );
+			}	
+
+			// if we come until here, childelement is a property value
+			Property prop = new Property (childElement.getTagName(), helmaNode);
+			if ( !"".equals(childElement.getAttribute("id")) || !"".equals(childElement.getAttribute("idref")) )	{
+				// we've got an object!
+				String idref = childElement.getAttribute("idref");
+				prop.setNodeHandle (new NodeHandle(new DbKey(null,idref)));
+				
+			}	else	{
+				String type = childElement.getAttribute("type");
+				String content = XmlUtil.getTextContent(childElement);
+				if ( type.equals("boolean") )	{
+					if ( content.equals("true") )	{
+						prop.setBooleanValue(true);
+					}	else	{
+						prop.setBooleanValue(false);
+					}
+				}	else if ( type.equals("date") )	{
+					SimpleDateFormat format = new SimpleDateFormat ( DATEFORMAT );
+					try	{
+						Date date = format.parse(content);
+						prop.setDateValue (date);
+					}	catch ( ParseException e )	{
+						prop.setStringValue (content);
+					}
+				}	else if ( type.equals("float") )	{
+					prop.setFloatValue ((new Double(content)).doubleValue());
+				}	else if ( type.equals("integer") )	{
+	    			prop.setIntegerValue ((new Long(content)).longValue());
+				}	else {
+	    			prop.setStringValue (content);
+				}
+			}
+   			propMap.put (childElement.getTagName(), prop);
+		}
+		if ( propMap.size()>0 )
+			helmaNode.setPropMap (propMap);
+		else
+			helmaNode.setPropMap (null);
+		if ( subnodes.size()>0 )
+			helmaNode.setSubnodes (subnodes);
+		else
+			helmaNode.setSubnodes (null);
+		return helmaNode;
+	}
 
 }
 

src/helma/objectmodel/dom/XmlUtil.java

@@ -10,6 +10,7 @@ import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.parsers.ParserConfigurationException;
 
 import org.w3c.dom.Document;
+import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.xml.sax.SAXException;
@@ -54,6 +55,24 @@ public class XmlUtil	{
 		}
 	}
 
+	/**
+	  * get first "real" element (ie not the document-rootelement, but the next one
+	  */
+	public static Element getFirstElement (Document document)	{
+		Element workelement = null;
+		if ( document.getDocumentElement()!=null )	{
+			org.w3c.dom.Node tmp = document.getDocumentElement().getFirstChild();
+			while( tmp!=null )	{
+				tmp = tmp.getNextSibling();
+				if ( tmp.getNodeType()==org.w3c.dom.Node.ELEMENT_NODE )	{
+					workelement = (Element) tmp;
+					break;
+				}
+			}
+		}
+		return workelement;
+	}
+
 	/**
 	  * return the text content of an element
 	  */

src/helma/objectmodel/dom/XmlWriter.java

@@ -1,11 +1,24 @@
 package helma.objectmodel.dom;
 
-import java.io.*;
+import java.io.File;
-import java.net.*;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.UnsupportedEncodingException;
 import java.text.SimpleDateFormat;
-import java.util.*;
+import java.util.Date;
+import java.util.Enumeration;
+import java.util.Hashtable;
+import java.util.Vector;
 
 import helma.objectmodel.*;
+import helma.objectmodel.INode;
+import helma.objectmodel.IProperty;
+import helma.objectmodel.TransientNode;
+import helma.objectmodel.db.Node;
+import helma.objectmodel.db.DbMapping;
 import helma.util.HtmlEncoder;
 
 public class XmlWriter extends OutputStreamWriter implements XmlConstants {
@@ -19,6 +32,9 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 	private StringBuffer prefix = new StringBuffer();
 
 	private static int fileid;
+ 	private SimpleDateFormat format = new SimpleDateFormat ( DATEFORMAT );
+
+	private boolean dbmode = true;
 
 	/**
 	  * create ids that can be used for temporary files.
@@ -38,14 +54,26 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		super(out);
 	}
 
+	public XmlWriter (OutputStream out, String enc) throws UnsupportedEncodingException {
+		super(out, enc);
+	}
+
 	public XmlWriter (String desc) throws FileNotFoundException {
 		super (new FileOutputStream (desc));
 	}
 
+	public XmlWriter (String desc, String enc) throws FileNotFoundException, UnsupportedEncodingException {
+		super (new FileOutputStream (desc), enc);
+	}
+
 	public XmlWriter (File file) throws FileNotFoundException {
 		super (new FileOutputStream (file));
 	}
 
+	public XmlWriter (File file, String enc) throws FileNotFoundException, UnsupportedEncodingException {
+		super (new FileOutputStream (file), enc);
+	}
+
 	/**
 	  * by default writing only descends 50 levels into the node tree to prevent
 	  * infite loops. number can be changed here.
@@ -54,6 +82,10 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		maxLevels = levels;
 	}
 
+	public void setDatabaseMode (boolean dbmode) {
+		this.dbmode = dbmode;
+	}
+
 	/**
 	  * set the number of space chars
 	  */
@@ -72,7 +104,8 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 	  */
 	public boolean write( INode node ) throws IOException {
 		convertedNodes = new Vector();
-		writeln ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
+		String encoding = getEncoding();
+		writeln ("<?xml version=\"1.0\" encoding=\""+encoding+"\"?>");
 		writeln ("<!-- printed by helma object publisher     -->");
 		writeln ("<!-- created " + (new Date()).toString() + " -->" );
 		write   ("<xmlroot xmlns:hop=\"");
@@ -86,17 +119,26 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 
 	/**
 	  * write a hopobject and print all its properties and children.
-      * if node has already been fully printed, just make a reference here.
+      * references are made here if a node already has been fully printed
+      * or if this is the last level that's going to be dumped
 	  */
 	public void write (INode node, String name, int level) throws IOException {
-		if ( ++level>maxLevels )
+		if (node==null)
 			return;
 		prefix.append(indent);
+		if ( ++level>maxLevels ) {
+			writeReferenceTag (node, name);
+			prefix = prefix.delete( prefix.length()-indent.length(), Integer.MAX_VALUE );
+			return;
+		}
 		if ( convertedNodes.contains(node) ) {
 			writeReferenceTag (node, name);
 		} else {
 			convertedNodes.addElement (node);
 			writeTagOpen  (node,name);
+			if ( node.getParent()!=null ) {
+				writeReferenceTag  (node.getParent(),"hop:parent");
+			}
 			writeProperties (node,level);
 			writeChildren (node,level);
 			writeTagClose (node,name);
@@ -104,12 +146,24 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		prefix = prefix.delete( prefix.length()-indent.length(), Integer.MAX_VALUE );
 	}
 
+
+
 	/**
 	  * loop through properties and print them with their property-name
 	  * as elementname
 	  */
 	private void writeProperties (INode node, int level) throws IOException {
-		Enumeration e = node.properties();
+		Enumeration e = null;
+		if ( dbmode==true && node instanceof helma.objectmodel.db.Node ) {
+			// a newly constructed db.Node doesn't have a propMap,
+			// but returns an enumeration of all it's db-mapped properties
+			Hashtable props = ((Node)node).getPropMap();
+			if (props==null)
+				return;
+			e = props.keys();
+		} else {
+			e = node.properties();
+		}
 		while ( e.hasMoreElements() ) {
 			String key = (String)e.nextElement();
 			IProperty prop = node.get(key,false);
@@ -129,7 +183,7 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		write (indent);
 		write ("<");
 		write (key);
-		write (" hop:type=\"null\"/>");
+		write (" type=\"null\"/>");
 		write (LINESEPARATOR);
 	}
 
@@ -144,18 +198,17 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		write (property.getName());
 		switch (property.getType()) {
 			case IProperty.BOOLEAN:
-				write (" hop:type=\"boolean\"");
+				write (" type=\"boolean\"");
 				break;
 			case IProperty.FLOAT:
-				write (" hop:type=\"float\"");
+				write (" type=\"float\"");
 				break;
 			case IProperty.INTEGER:
-				write (" hop:type=\"integer\"");
+				write (" type=\"integer\"");
 				break;
 		}
 		if ( property.getType()==IProperty.DATE ) {
-			write (" hop:type=\"date\"");
+			write (" type=\"date\"");
-			SimpleDateFormat format = new SimpleDateFormat ( DATEFORMAT );
 			write (">");
 			write ( format.format (property.getDateValue()) );
 		} else {
@@ -172,6 +225,12 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 	  * loop through the children-array and print them as <hop:child>
 	  */
 	private void writeChildren (INode node, int level) throws IOException {
+		if ( dbmode==true && node instanceof helma.objectmodel.db.Node ) {
+			Node dbNode = (Node)node;
+			DbMapping smap = dbNode.getDbMapping() == null ? null : dbNode.getDbMapping().getSubnodeMapping ();
+			if (smap != null && smap.isRelational ())
+				return;
+		}
 		Enumeration e = node.getSubnodes();
 		while (e.hasMoreElements()) {
 			INode nextNode = (INode)e.nextElement();
@@ -187,12 +246,18 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 		write (prefix.toString());
 		write ("<");
 		write ( (name==null)?"hopobject" : name);
-		write (" hop:id=\"");
+		write (" id=\"");
 		write (getNodeIdentifier(node));
-		write ("\" hop:prototype=\"");
+		write ("\" name=\"");
+		write (node.getName());
+		write ("\" prototype=\"");
 		write (getNodePrototype(node));
-		write ("\"");
+		write ("\" created=\"");
-		write (">");
+		write (Long.toString(node.created()));
+		write ("\" lastModified=\"");
+		write (Long.toString(node.lastModified()));
+		//FIXME: do we need anonymous-property?
+		write ("\">");
 		write (LINESEPARATOR);
 	}
 
@@ -210,16 +275,16 @@ public class XmlWriter	extends OutputStreamWriter implements XmlConstants		{
 
 	/**
 	  * write a tag holding a reference to an element that has
-	  * been dumped before.
+	  * been written out before.
-	  * e.g. <parent hop:idref="t35" hop:prototyperef="hopobject"/>
+	  * e.g. <parent idref="35" prototyperef="hopobject"/>
 	  */
 	public void writeReferenceTag (INode node, String name) throws IOException {
 		write (prefix.toString());
 		write ("<");
 		write ( (name==null)?"hopobject" : name);
-		write ( " hop:idref=\"");
+		write ( " idref=\"");
 		write (getNodeIdentifier(node));
-		write ("\" hop:prototyperef=\"");
+		write ("\" prototyperef=\"");
 		write (getNodePrototype(node));
 		write ("\"");
 		write ("/>");