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Subject: svn commit: r386838 - in
 /incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db:
 DatabasePersistenceManager.java JNDIDatabasePersistenceManager.java
 SimpleDbPersistenceManager.java
Date: Sat, 18 Mar 2006 10:43:55 -0000
To: jackrabbit-commits@incubator.apache.org
From: jukka@apache.org

Author: jukka
Date: Sat Mar 18 02:43:52 2006
New Revision: 386838

URL: http://svn.apache.org/viewcvs?rev=386838&view=rev
Log:
JCR-313: Extracted common database PM functionality to an abstract DatabasePersitenceManager class. Added a JNDIDatabasePersistenceManager class.

Added:
    incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/DatabasePersistenceManager.java
      - copied, changed from r386833, incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java
    incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java   (with props)
Modified:
    incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java

Copied: incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/DatabasePersistenceManager.java (from r386833, incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java)
URL: http://svn.apache.org/viewcvs/incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/DatabasePersistenceManager.java?p2=incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/DatabasePersistenceManager.java&p1=incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java&r1=386833&r2=386838&rev=386838&view=diff
==============================================================================
--- incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java (original)
+++ incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/DatabasePersistenceManager.java Sat Mar 18 02:43:52 2006
@@ -50,7 +50,6 @@
 import java.io.FilterInputStream;
 import java.io.ByteArrayInputStream;
 import java.sql.Connection;
-import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -58,108 +57,25 @@
 import java.sql.DatabaseMetaData;
 
 /**
- * <code>SimpleDbPersistenceManager</code> is a generic JDBC-based
- * <code>PersistenceManager</code> for Jackrabbit that persists
- * <code>ItemState</code> and <code>NodeReferences</code> objects using a
- * simple custom binary serialization format (see {@link Serializer}) and a
- * very basic non-normalized database schema (in essence tables with one 'key'
- * and one 'data' column).
- * <p/>
- * It is configured through the following properties:
- * <ul>
- * <li><code>driver</code>: the FQN name of the JDBC driver class</li>
- * <li><code>url</code>: the database url of the form <code>jdbc:subprotocol:subname</code></li>
- * <li><code>user</code>: the database user</li>
- * <li><code>password</code>: the user's password</li>
- * <li><code>schema</code>: type of schema to be used
- * (e.g. <code>mysql</code>, <code>mssql</code>, etc.); </li>
- * <li><code>schemaObjectPrefix</code>: prefix to be prepended to schema objects</li>
- * <li><code>externalBLOBs</code>: if <code>true</code> (the default) BINARY
- * values (BLOBs) are stored in the local file system;
- * if <code>false</code> BLOBs are stored in the database</li>
- * </ul>
- * The required schema objects are automatically created by executing the DDL
- * statements read from the [schema].ddl file. The .ddl file is read from the
- * resources by calling <code>getClass().getResourceAsStream(schema + ".ddl")</code>.
- * Every line in the specified .ddl file is executed separatly by calling
- * <code>java.sql.Statement.execute(String)</code> where every occurence of the
- * the string <code>"${schemaObjectPrefix}"</code> has been replaced with the
- * value of the property <code>schemaObjectPrefix</code>.
- * <p/>
- * The following is a fragment from a sample configuration using MySQL:
- * <pre>
- *   &lt;PersistenceManager class="org.apache.jackrabbit.core.state.db.SimpleDbPersistenceManager"&gt;
- *       &lt;param name="driver" value="com.mysql.jdbc.Driver"/&gt;
- *       &lt;param name="url" value="jdbc:mysql:///test"/&gt;
- *       &lt;param name="schema" value="mysql"/&gt;
- *       &lt;param name="schemaObjectPrefix" value="${wsp.name}_"/&gt;
- *       &lt;param name="externalBLOBs" value="false"/&gt;
- *   &lt;/PersistenceManager&gt;
- * </pre>
- * The following is a fragment from a sample configuration using Daffodil One$DB Embedded:
- * <pre>
- *   &lt;PersistenceManager class="org.apache.jackrabbit.core.state.db.SimpleDbPersistenceManager"&gt;
- *       &lt;param name="driver" value="in.co.daffodil.db.jdbc.DaffodilDBDriver"/&gt;
- *       &lt;param name="url" value="jdbc:daffodilDB_embedded:${wsp.name};path=${wsp.home}/../../databases;create=true"/&gt;
- *       &lt;param name="user" value="daffodil"/&gt;
- *       &lt;param name="password" value="daffodil"/&gt;
- *       &lt;param name="schema" value="daffodil"/&gt;
- *       &lt;param name="schemaObjectPrefix" value="${wsp.name}_"/&gt;
- *       &lt;param name="externalBLOBs" value="false"/&gt;
- *   &lt;/PersistenceManager&gt;
- * </pre>
- * The following is a fragment from a sample configuration using DB2:
- * <pre>
- *   &lt;PersistenceManager class="org.apache.jackrabbit.core.state.db.SimpleDbPersistenceManager"&gt;
- *       &lt;param name="driver" value="com.ibm.db2.jcc.DB2Driver"/&gt;
- *       &lt;param name="url" value="jdbc:db2:test"/&gt;
- *       &lt;param name="schema" value="db2"/&gt;
- *       &lt;param name="schemaObjectPrefix" value="${wsp.name}_"/&gt;
- *       &lt;param name="externalBLOBs" value="false"/&gt;
- *   &lt;/PersistenceManager&gt;
- * </pre>
- * The following is a fragment from a sample configuration using MSSQL:
- * <pre>
- *   &lt;PersistenceManager class="org.apache.jackrabbit.core.state.db.SimpleDbPersistenceManager"&gt;
- *       &lt;param name="driver" value="com.microsoft.jdbc.sqlserver.SQLServerDriver"/&gt;
- *       &lt;param name="url" value="jdbc:microsoft:sqlserver://localhost:1433;;DatabaseName=test;SelectMethod=Cursor;"/&gt;
- *       &lt;param name="schema" value="mssql"/&gt;
- *       &lt;param name="user" value="sa"/&gt;
- *       &lt;param name="password" value=""/&gt;
- *       &lt;param name="schemaObjectPrefix" value="${wsp.name}_"/&gt;
- *       &lt;param name="externalBLOBs" value="false"/&gt;
- *   &lt;/PersistenceManager&gt;
- * </pre>
- * The following is a fragment from a sample configuration using PostgreSQL:
- * <pre>
- *   &lt;PersistenceManager class="org.apache.jackrabbit.core.state.db.SimpleDbPersistenceManager"&gt;
- *       &lt;param name="driver" value="org.postgresql.Driver"/&gt;
- *       &lt;param name="url" value="jdbc:postgresql://localhost/test"/&gt;
- *       &lt;param name="schema" value="postgresql"/&gt;
- *       &lt;param name="user" value="postgres"/&gt;
- *       &lt;param name="password" value="postgres"/&gt;
- *       &lt;param name="schemaObjectPrefix" value="${wsp.name}_"/&gt;
- *       &lt;param name="externalBLOBs" value="false"/&gt;
- *   &lt;/PersistenceManager&gt;
- * </pre>
- * See also {@link DerbyPersistenceManager}.
+ * Abstract base class for database persistence managers. This class
+ * contains common functionality for database persistence manager subclasses
+ * that normally differ only in the way the database connection is acquired.
+ * <p>
+ * See the {@link SimpleDbPersistenceManager} for a detailed description
+ * of the available configuration options and database behaviour.
  */
-public class SimpleDbPersistenceManager extends AbstractPersistenceManager {
+public abstract class DatabasePersistenceManager extends AbstractPersistenceManager {
 
     /**
      * Logger instance
      */
-    private static Logger log = LoggerFactory.getLogger(SimpleDbPersistenceManager.class);
+    private static Logger log = LoggerFactory.getLogger(DatabasePersistenceManager.class);
 
     protected static final String SCHEMA_OBJECT_PREFIX_VARIABLE =
             "${schemaObjectPrefix}";
 
     protected boolean initialized;
 
-    protected String driver;
-    protected String url;
-    protected String user;
-    protected String password;
     protected String schema;
     protected String schemaObjectPrefix;
 
@@ -212,9 +128,9 @@
     protected BLOBStore blobStore;
 
     /**
-     * Creates a new <code>SimpleDbPersistenceManager</code> instance.
+     * Creates a new <code>DatabasePersistenceManager</code> instance.
      */
-    public SimpleDbPersistenceManager() {
+    public DatabasePersistenceManager() {
         schema = "default";
         schemaObjectPrefix = "";
         externalBLOBs = true;
@@ -222,37 +138,6 @@
     }
 
     //----------------------------------------------------< setters & getters >
-    public String getUrl() {
-        return url;
-    }
-
-    public void setUrl(String url) {
-        this.url = url;
-    }
-
-    public String getUser() {
-        return user;
-    }
-
-    public void setUser(String user) {
-        this.user = user;
-    }
-
-    public String getPassword() {
-        return password;
-    }
-
-    public void setPassword(String password) {
-        this.password = password;
-    }
-
-    public String getDriver() {
-        return driver;
-    }
-
-    public void setDriver(String driver) {
-        this.driver = driver;
-    }
 
     public String getSchemaObjectPrefix() {
         return schemaObjectPrefix;
@@ -293,7 +178,8 @@
         }
 
         // setup jdbc connection
-        initConnection();
+        con = getConnection();
+        con.setAutoCommit(false);
 
         // make sure schemaObjectPrefix consists of legal name characters only
         prepareSchemaObjectPrefix();
@@ -902,13 +788,10 @@
     /**
      * Initialize the JDBC connection.
      *
+     * @return new connection
      * @throws Exception if an error occurs
      */
-    protected void initConnection() throws Exception {
-        Class.forName(driver);
-        con = DriverManager.getConnection(url, user, password);
-        con.setAutoCommit(false);
-    }
+    abstract Connection getConnection() throws Exception;
 
     /**
      * Resets the given <code>PreparedStatement</code> by clearing the parameters

Added: incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java
URL: http://svn.apache.org/viewcvs/incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java?rev=386838&view=auto
==============================================================================
--- incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java (added)
+++ incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java Sat Mar 18 02:43:52 2006
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2004-2005 The Apache Software Foundation or its licensors,
+ *                     as applicable.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.jackrabbit.core.state.db;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import javax.naming.InitialContext;
+import javax.naming.NamingException;
+import javax.sql.DataSource;
+
+/**
+ * Database persistence manager that uses JNDI to acquire the database
+ * connection. The JNDI location of the {@link DataSource} to be used in
+ * given as the <code>dataSourceLocation</code> configuration property.
+ * See the {@link SimpleDbPersistenceManager} for more configuration
+ * details.
+ * <p>
+ * <strong>WARNING:</strong> The acquired database connection is kept
+ * for the entire lifetime of the persistence manager instance. The
+ * configured data source should be prepared for this. 
+ */
+public class JNDIDatabasePersistenceManager extends DatabasePersistenceManager {
+
+    /**
+     * JNDI location of the data source used to acquire database connections.
+     */
+    private String dataSourceLocation;
+
+    //----------------------------------------------------< setters & getters >
+
+    /**
+     * Returns the JNDI location of the data source.
+     *
+     * @return data source location
+     */
+    public String getDataSourceLocation() {
+        return dataSourceLocation;
+    }
+
+    /**
+     * Sets the JNDI location of the data source.
+     *
+     * @param dataSourceLocation data source location
+     */
+    public void setDataSourceLocation(String dataSourceLocation) {
+        this.dataSourceLocation = dataSourceLocation;
+    }
+
+    //-------------------------------------------< DatabasePersistenceManager >
+
+    /**
+     * Returns a JDBC connection from a {@link DataSource} acquired from JNDI
+     * with the configured data source location.
+     *
+     * @return new database connection
+     * @throws NamingException if the given data source location does not exist
+     * @throws Exception if a database access error occurs
+     * @see DatabasePersistenceManager#getConnection()
+     */
+    protected Connection getConnection() throws NamingException, SQLException {
+        InitialContext ic = new InitialContext();
+        DataSource dataSource = (DataSource) ic.lookup(dataSourceLocation);
+        return dataSource.getConnection();
+    }
+
+}

Propchange: incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/JNDIDatabasePersistenceManager.java
------------------------------------------------------------------------------
    svn:eol-style = native

Modified: incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java
URL: http://svn.apache.org/viewcvs/incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java?rev=386838&r1=386837&r2=386838&view=diff
==============================================================================
--- incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java (original)
+++ incubator/jackrabbit/trunk/jackrabbit/src/main/java/org/apache/jackrabbit/core/state/db/SimpleDbPersistenceManager.java Sat Mar 18 02:43:52 2006
@@ -16,46 +16,11 @@
  */
 package org.apache.jackrabbit.core.state.db;
 
-import org.apache.jackrabbit.core.NodeId;
-import org.apache.jackrabbit.core.PropertyId;
-import org.apache.jackrabbit.core.fs.FileSystem;
-import org.apache.jackrabbit.core.fs.local.LocalFileSystem;
-import org.apache.jackrabbit.core.state.AbstractPersistenceManager;
-import org.apache.jackrabbit.core.state.ChangeLog;
-import org.apache.jackrabbit.core.state.ItemStateException;
-import org.apache.jackrabbit.core.state.NoSuchItemStateException;
-import org.apache.jackrabbit.core.state.NodeReferences;
-import org.apache.jackrabbit.core.state.NodeReferencesId;
-import org.apache.jackrabbit.core.state.NodeState;
-import org.apache.jackrabbit.core.state.PMContext;
-import org.apache.jackrabbit.core.state.PropertyState;
-import org.apache.jackrabbit.core.state.ItemState;
-import org.apache.jackrabbit.core.state.util.BLOBStore;
-import org.apache.jackrabbit.core.state.util.FileSystemBLOBStore;
-import org.apache.jackrabbit.core.state.util.Serializer;
-import org.apache.jackrabbit.core.value.BLOBFileValue;
-import org.apache.jackrabbit.core.value.InternalValue;
-import org.apache.jackrabbit.util.Text;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.jcr.PropertyType;
-import javax.jcr.RepositoryException;
-import java.io.BufferedReader;
-import java.io.ByteArrayOutputStream;
-import java.io.File;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.FilterInputStream;
-import java.io.ByteArrayInputStream;
 import java.sql.Connection;
 import java.sql.DriverManager;
-import java.sql.PreparedStatement;
-import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.sql.Statement;
-import java.sql.DatabaseMetaData;
+
+import org.apache.jackrabbit.core.state.util.Serializer;
 
 /**
  * <code>SimpleDbPersistenceManager</code> is a generic JDBC-based
@@ -144,82 +109,12 @@
  * </pre>
  * See also {@link DerbyPersistenceManager}.
  */
-public class SimpleDbPersistenceManager extends AbstractPersistenceManager {
-
-    /**
-     * Logger instance
-     */
-    private static Logger log = LoggerFactory.getLogger(SimpleDbPersistenceManager.class);
-
-    protected static final String SCHEMA_OBJECT_PREFIX_VARIABLE =
-            "${schemaObjectPrefix}";
-
-    protected boolean initialized;
+public class SimpleDbPersistenceManager extends DatabasePersistenceManager {
 
     protected String driver;
     protected String url;
     protected String user;
     protected String password;
-    protected String schema;
-    protected String schemaObjectPrefix;
-
-    protected boolean externalBLOBs;
-
-    // initial size of buffer used to serialize objects
-    protected static final int INITIAL_BUFFER_SIZE = 1024;
-
-    // jdbc connection
-    protected Connection con;
-
-    // shared prepared statements for NodeState management
-    protected PreparedStatement nodeStateInsert;
-    protected PreparedStatement nodeStateUpdate;
-    protected PreparedStatement nodeStateSelect;
-    protected PreparedStatement nodeStateSelectExist;
-    protected PreparedStatement nodeStateDelete;
-
-    // shared prepared statements for PropertyState management
-    protected PreparedStatement propertyStateInsert;
-    protected PreparedStatement propertyStateUpdate;
-    protected PreparedStatement propertyStateSelect;
-    protected PreparedStatement propertyStateSelectExist;
-    protected PreparedStatement propertyStateDelete;
-
-    // shared prepared statements for NodeReference management
-    protected PreparedStatement nodeReferenceInsert;
-    protected PreparedStatement nodeReferenceUpdate;
-    protected PreparedStatement nodeReferenceSelect;
-    protected PreparedStatement nodeReferenceSelectExist;
-    protected PreparedStatement nodeReferenceDelete;
-
-    // shared prepared statements for BLOB management
-    // (if <code>externalBLOBs==false</code>)
-    protected PreparedStatement blobInsert;
-    protected PreparedStatement blobUpdate;
-    protected PreparedStatement blobSelect;
-    protected PreparedStatement blobSelectExist;
-    protected PreparedStatement blobDelete;
-
-    /**
-     * file system where BLOB data is stored
-     * (if <code>externalBLOBs==true</code>)
-     */
-    protected FileSystem blobFS;
-    /**
-     * BLOBStore that manages BLOB data in the file system
-     * (if <code>externalBLOBs==true</code>)
-     */
-    protected BLOBStore blobStore;
-
-    /**
-     * Creates a new <code>SimpleDbPersistenceManager</code> instance.
-     */
-    public SimpleDbPersistenceManager() {
-        schema = "default";
-        schemaObjectPrefix = "";
-        externalBLOBs = true;
-        initialized = false;
-    }
 
     //----------------------------------------------------< setters & getters >
     public String getUrl() {
@@ -254,892 +149,19 @@
         this.driver = driver;
     }
 
-    public String getSchemaObjectPrefix() {
-        return schemaObjectPrefix;
-    }
-
-    public void setSchemaObjectPrefix(String schemaObjectPrefix) {
-        // make sure prefix is all uppercase
-        this.schemaObjectPrefix = schemaObjectPrefix.toUpperCase();
-    }
-
-    public String getSchema() {
-        return schema;
-    }
-
-    public void setSchema(String schema) {
-        this.schema = schema;
-    }
-
-    public boolean isExternalBLOBs() {
-        return externalBLOBs;
-    }
-
-    public void setExternalBLOBs(boolean externalBLOBs) {
-        this.externalBLOBs = externalBLOBs;
-    }
-
-    public void setExternalBLOBs(String externalBLOBs) {
-        this.externalBLOBs = Boolean.valueOf(externalBLOBs).booleanValue();
-    }
-
-    //---------------------------------------------------< PersistenceManager >
-    /**
-     * {@inheritDoc}
-     */
-    public void init(PMContext context) throws Exception {
-        if (initialized) {
-            throw new IllegalStateException("already initialized");
-        }
-
-        // setup jdbc connection
-        initConnection();
-
-        // make sure schemaObjectPrefix consists of legal name characters only
-        prepareSchemaObjectPrefix();
-
-        // check if schema objects exist and create them if necessary
-        checkSchema();
-
-        // prepare statements
-        nodeStateInsert =
-                con.prepareStatement("insert into "
-                + schemaObjectPrefix + "NODE (NODE_DATA, NODE_ID) values (?, ?)");
-        nodeStateUpdate =
-                con.prepareStatement("update "
-                + schemaObjectPrefix + "NODE set NODE_DATA = ? where NODE_ID = ?");
-        nodeStateSelect =
-                con.prepareStatement("select NODE_DATA from "
-                + schemaObjectPrefix + "NODE where NODE_ID = ?");
-        nodeStateSelectExist =
-                con.prepareStatement("select 1 from "
-                + schemaObjectPrefix + "NODE where NODE_ID = ?");
-        nodeStateDelete =
-                con.prepareStatement("delete from "
-                + schemaObjectPrefix + "NODE where NODE_ID = ?");
-
-        propertyStateInsert =
-                con.prepareStatement("insert into "
-                + schemaObjectPrefix + "PROP (PROP_DATA, PROP_ID) values (?, ?)");
-        propertyStateUpdate =
-                con.prepareStatement("update "
-                + schemaObjectPrefix + "PROP set PROP_DATA = ? where PROP_ID = ?");
-        propertyStateSelect =
-                con.prepareStatement("select PROP_DATA from "
-                + schemaObjectPrefix + "PROP where PROP_ID = ?");
-        propertyStateSelectExist =
-                con.prepareStatement("select 1 from "
-                + schemaObjectPrefix + "PROP where PROP_ID = ?");
-        propertyStateDelete =
-                con.prepareStatement("delete from "
-                + schemaObjectPrefix + "PROP where PROP_ID = ?");
-
-        nodeReferenceInsert =
-                con.prepareStatement("insert into "
-                + schemaObjectPrefix + "REFS (REFS_DATA, NODE_ID) values (?, ?)");
-        nodeReferenceUpdate =
-                con.prepareStatement("update "
-                + schemaObjectPrefix + "REFS set REFS_DATA = ? where NODE_ID = ?");
-        nodeReferenceSelect =
-                con.prepareStatement("select REFS_DATA from "
-                + schemaObjectPrefix + "REFS where NODE_ID = ?");
-        nodeReferenceSelectExist =
-                con.prepareStatement("select 1 from "
-                + schemaObjectPrefix + "REFS where NODE_ID = ?");
-        nodeReferenceDelete =
-                con.prepareStatement("delete from "
-                + schemaObjectPrefix + "REFS where NODE_ID = ?");
-
-        if (externalBLOBs) {
-            /**
-             * store BLOBs in local file system in a sub directory
-             * of the workspace home directory
-             */
-            LocalFileSystem blobFS = new LocalFileSystem();
-            blobFS.setRoot(new File(context.getHomeDir(), "blobs"));
-            blobFS.init();
-            this.blobFS = blobFS;
-            blobStore = new FileSystemBLOBStore(blobFS);
-        } else {
-            /**
-             * store BLOBs in db
-             */
-            blobStore = new DbBLOBStore();
-
-            blobInsert =
-                    con.prepareStatement("insert into "
-                    + schemaObjectPrefix + "BINVAL (BINVAL_DATA, BINVAL_ID) values (?, ?)");
-            blobUpdate =
-                    con.prepareStatement("update "
-                    + schemaObjectPrefix + "BINVAL set BINVAL_DATA = ? where BINVAL_ID = ?");
-            blobSelect =
-                    con.prepareStatement("select BINVAL_DATA from "
-                    + schemaObjectPrefix + "BINVAL where BINVAL_ID = ?");
-            blobSelectExist =
-                    con.prepareStatement("select 1 from "
-                    + schemaObjectPrefix + "BINVAL where BINVAL_ID = ?");
-            blobDelete =
-                    con.prepareStatement("delete from "
-                    + schemaObjectPrefix + "BINVAL where BINVAL_ID = ?");
-        }
-
-        initialized = true;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public synchronized void close() throws Exception {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        try {
-            // close shared prepared statements
-            closeStatement(nodeStateInsert);
-            closeStatement(nodeStateUpdate);
-            closeStatement(nodeStateSelect);
-            closeStatement(nodeStateSelectExist);
-            closeStatement(nodeStateDelete);
-
-            closeStatement(propertyStateInsert);
-            closeStatement(propertyStateUpdate);
-            closeStatement(propertyStateSelect);
-            closeStatement(propertyStateSelectExist);
-            closeStatement(propertyStateDelete);
-
-            closeStatement(nodeReferenceInsert);
-            closeStatement(nodeReferenceUpdate);
-            closeStatement(nodeReferenceSelect);
-            closeStatement(nodeReferenceSelectExist);
-            closeStatement(nodeReferenceDelete);
-
-            if (!externalBLOBs) {
-                closeStatement(blobInsert);
-                closeStatement(blobUpdate);
-                closeStatement(blobSelect);
-                closeStatement(blobSelectExist);
-                closeStatement(blobDelete);
-            } else {
-                // close BLOB file system
-                blobFS.close();
-                blobFS = null;
-            }
-            blobStore = null;
-
-            // close jdbc connection
-            con.close();
-
-        } finally {
-            initialized = false;
-        }
-    }
+    //------------------------------------------< DatabasePersistenceManager >
 
     /**
-     * {@inheritDoc}
-     */
-    public synchronized void store(ChangeLog changeLog)
-            throws ItemStateException {
-        ItemStateException ise = null;
-        try {
-            super.store(changeLog);
-        } catch (ItemStateException e) {
-            ise = e;
-        } finally {
-            if (ise == null) {
-                // storing the changes succeeded, now commit the changes
-                try {
-                    con.commit();
-                } catch (SQLException e) {
-                    String msg = "committing change log failed";
-                    log.error(msg, e);
-                    throw new ItemStateException(msg, e);
-                }
-            } else {
-                // storing the changes failed, rollback changes
-                try {
-                    con.rollback();
-                } catch (SQLException e) {
-                    String msg = "rollback of change log failed";
-                    log.error(msg, e);
-                }
-                // re-throw original exception
-                throw ise;
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public NodeState load(NodeId id)
-            throws NoSuchItemStateException, ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeStateSelect;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            InputStream in = null;
-            try {
-                stmt.setString(1, id.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-                if (!rs.next()) {
-                    throw new NoSuchItemStateException(id.toString());
-                }
-
-                in = rs.getBinaryStream(1);
-                NodeState state = createNew(id);
-                Serializer.deserialize(state, in);
-
-                return state;
-            } catch (Exception e) {
-                if (e instanceof NoSuchItemStateException) {
-                    throw (NoSuchItemStateException) e;
-                }
-                String msg = "failed to read node state: " + id;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeStream(in);
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public PropertyState load(PropertyId id)
-            throws NoSuchItemStateException, ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = propertyStateSelect;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            InputStream in = null;
-            try {
-                stmt.setString(1, id.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-                if (!rs.next()) {
-                    throw new NoSuchItemStateException(id.toString());
-                }
-
-                in = rs.getBinaryStream(1);
-                PropertyState state = createNew(id);
-                Serializer.deserialize(state, in, blobStore);
-
-                return state;
-            } catch (Exception e) {
-                if (e instanceof NoSuchItemStateException) {
-                    throw (NoSuchItemStateException) e;
-                }
-                String msg = "failed to read property state: " + id;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeStream(in);
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     * <p/>
-     * This method uses shared <code>PreparedStatement</code>s which must
-     * be executed strictly sequentially. Because this method synchronizes on
-     * the persistence manager instance there is no need to synchronize on the
-     * shared statement. If the method would not be sychronized the shared
-     * statements would have to be synchronized.
-     */
-    public synchronized void store(NodeState state) throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        // check if insert or update
-        boolean update = state.getStatus() != ItemState.STATUS_NEW;
-        //boolean update = exists(state.getId());
-        PreparedStatement stmt = (update) ? nodeStateUpdate : nodeStateInsert;
-
-        try {
-            ByteArrayOutputStream out =
-                    new ByteArrayOutputStream(INITIAL_BUFFER_SIZE);
-            // serialize node state
-            Serializer.serialize(state, out);
-
-            // we are synchronized on this instance, therefore we do not
-            // not have to additionally synchronize on the preparedStatement
-
-            stmt.setBytes(1, out.toByteArray());
-            stmt.setString(2, state.getNodeId().toString());
-            stmt.executeUpdate();
-
-            // there's no need to close a ByteArrayOutputStream
-            //out.close();
-        } catch (Exception e) {
-            String msg = "failed to write node state: " + state.getNodeId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     * <p/>
-     * This method uses shared <code>PreparedStatement</code>s which must
-     * be executed strictly sequentially. Because this method synchronizes on
-     * the persistence manager instance there is no need to synchronize on the
-     * shared statement. If the method would not be sychronized the shared
-     * statements would have to be synchronized.
-     */
-    public synchronized void store(PropertyState state)
-            throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        // check if insert or update
-        boolean update = state.getStatus() != ItemState.STATUS_NEW;
-        //boolean update = exists(state.getId());
-        PreparedStatement stmt = (update) ? propertyStateUpdate : propertyStateInsert;
-
-        try {
-            ByteArrayOutputStream out =
-                    new ByteArrayOutputStream(INITIAL_BUFFER_SIZE);
-            // serialize property state
-            Serializer.serialize(state, out, blobStore);
-
-            // we are synchronized on this instance, therefore we do not
-            // not have to additionally synchronize on the preparedStatement
-
-            stmt.setBytes(1, out.toByteArray());
-            stmt.setString(2, state.getPropertyId().toString());
-            stmt.executeUpdate();
-
-            // there's no need to close a ByteArrayOutputStream
-            //out.close();
-        } catch (Exception e) {
-            String msg = "failed to write property state: " + state.getPropertyId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public synchronized void destroy(NodeState state)
-            throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeStateDelete;
-        try {
-            stmt.setString(1, state.getNodeId().toString());
-            stmt.executeUpdate();
-        } catch (Exception e) {
-            String msg = "failed to delete node state: " + state.getNodeId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public synchronized void destroy(PropertyState state)
-            throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        // make sure binary values (BLOBs) are properly removed
-        InternalValue[] values = state.getValues();
-        if (values != null) {
-            for (int i = 0; i < values.length; i++) {
-                InternalValue val = values[i];
-                if (val != null) {
-                    if (val.getType() == PropertyType.BINARY) {
-                        BLOBFileValue blobVal = (BLOBFileValue) val.internalValue();
-                        // delete internal resource representation of BLOB value
-                        blobVal.delete(true);
-                        // also remove from BLOBStore
-                        String blobId = blobStore.createId(state.getPropertyId(), i);
-                        try {
-                            blobStore.remove(blobId);
-                        } catch (Exception e) {
-                            log.warn("failed to remove from BLOBStore: " + blobId, e);
-                        }
-                    }
-                }
-            }
-        }
-
-        PreparedStatement stmt = propertyStateDelete;
-        try {
-            stmt.setString(1, state.getPropertyId().toString());
-            stmt.executeUpdate();
-        } catch (Exception e) {
-            String msg = "failed to delete property state: " + state.getPropertyId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public NodeReferences load(NodeReferencesId targetId)
-            throws NoSuchItemStateException, ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeReferenceSelect;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            InputStream in = null;
-            try {
-                stmt.setString(1, targetId.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-                if (!rs.next()) {
-                    throw new NoSuchItemStateException(targetId.toString());
-                }
-
-                in = rs.getBinaryStream(1);
-                NodeReferences refs = new NodeReferences(targetId);
-                Serializer.deserialize(refs, in);
-
-                return refs;
-            } catch (Exception e) {
-                if (e instanceof NoSuchItemStateException) {
-                    throw (NoSuchItemStateException) e;
-                }
-                String msg = "failed to read node references: " + targetId;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeStream(in);
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     * <p/>
-     * This method uses shared <code>PreparedStatement</code>s which must
-     * be executed strictly sequentially. Because this method synchronizes on
-     * the persistence manager instance there is no need to synchronize on the
-     * shared statement. If the method would not be sychronized the shared
-     * statements would have to be synchronized.
-     */
-    public synchronized void store(NodeReferences refs)
-            throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        // check if insert or update
-        boolean update = exists(refs.getId());
-        PreparedStatement stmt = (update) ? nodeReferenceUpdate : nodeReferenceInsert;
-
-        try {
-            ByteArrayOutputStream out =
-                    new ByteArrayOutputStream(INITIAL_BUFFER_SIZE);
-            // serialize references
-            Serializer.serialize(refs, out);
-
-            // we are synchronized on this instance, therefore we do not
-            // not have to additionally synchronize on the preparedStatement
-
-            stmt.setBytes(1, out.toByteArray());
-            stmt.setString(2, refs.getId().toString());
-            stmt.executeUpdate();
-
-            // there's no need to close a ByteArrayOutputStream
-            //out.close();
-        } catch (Exception e) {
-            String msg = "failed to write node references: " + refs.getId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public synchronized void destroy(NodeReferences refs)
-            throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeReferenceDelete;
-        try {
-            stmt.setString(1, refs.getId().toString());
-            stmt.executeUpdate();
-        } catch (Exception e) {
-            String msg = "failed to delete node references: " + refs.getId();
-            log.error(msg, e);
-            throw new ItemStateException(msg, e);
-        } finally {
-            resetStatement(stmt);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public boolean exists(NodeId id) throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeStateSelectExist;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            try {
-                stmt.setString(1, id.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-
-                // a node state exists if the result has at least one entry
-                return rs.next();
-            } catch (Exception e) {
-                String msg = "failed to check existence of node state: " + id;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public boolean exists(PropertyId id) throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = propertyStateSelectExist;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            try {
-                stmt.setString(1, id.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-
-                // a property state exists if the result has at least one entry
-                return rs.next();
-            } catch (Exception e) {
-                String msg = "failed to check existence of property state: " + id;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public boolean exists(NodeReferencesId targetId) throws ItemStateException {
-        if (!initialized) {
-            throw new IllegalStateException("not initialized");
-        }
-
-        PreparedStatement stmt = nodeReferenceSelectExist;
-        synchronized(stmt) {
-            ResultSet rs = null;
-            try {
-                stmt.setString(1, targetId.toString());
-                stmt.execute();
-                rs = stmt.getResultSet();
-
-                // a reference exists if the result has at least one entry
-                return rs.next();
-            } catch (Exception e) {
-                String msg = "failed to check existence of node references: "
-                        + targetId;
-                log.error(msg, e);
-                throw new ItemStateException(msg, e);
-            } finally {
-                closeResultSet(rs);
-                resetStatement(stmt);
-            }
-        }
-    }
-
-    //----------------------------------< misc. helper methods & overridables >
-    /**
-     * Initialize the JDBC connection.
+     * Returns a JDBC connection acquired using the JDBC {@link DriverManager}.
      *
-     * @throws Exception if an error occurs
+     * @throws ClassNotFoundException if the JDBC driver class is not found
+     * @throws SQLException if a database access error occurs
+     * @see DatabasePersistenceManager#getConnection()
      */
-    protected void initConnection() throws Exception {
+    protected Connection getConnection() throws ClassNotFoundException, SQLException {
         Class.forName(driver);
-        con = DriverManager.getConnection(url, user, password);
-        con.setAutoCommit(false);
-    }
-
-    /**
-     * Resets the given <code>PreparedStatement</code> by clearing the parameters
-     * and warnings contained.
-     * <p/>
-     * NOTE: This method MUST be called in a synchronized context as neither
-     * this method nor the <code>PreparedStatement</code> instance on which it
-     * operates are thread safe.
-     *
-     * @param stmt The <code>PreparedStatement</code> to reset. If
-     *             <code>null</code> this method does nothing.
-     */
-    protected void resetStatement(PreparedStatement stmt) {
-        if (stmt != null) {
-            try {
-                stmt.clearParameters();
-                stmt.clearWarnings();
-            } catch (SQLException se) {
-                logException("failed resetting PreparedStatement", se);
-            }
-        }
-    }
-
-    protected void closeResultSet(ResultSet rs) {
-        if (rs != null) {
-            try {
-                rs.close();
-            } catch (SQLException se) {
-                logException("failed closing ResultSet", se);
-            }
-        }
-    }
-
-    protected void closeStream(InputStream in) {
-        if (in != null) {
-            try {
-                in.close();
-            } catch (IOException ignore) {
-            }
-        }
-    }
-
-    protected void closeStatement(Statement stmt) {
-        if (stmt != null) {
-            try {
-                stmt.close();
-            } catch (SQLException se) {
-                logException("failed closing Statement", se);
-            }
-        }
-    }
-
-    protected void logException(String message, SQLException se) {
-        if (message != null) {
-            log.error(message);
-        }
-        log.error("    reason: " + se.getMessage());
-        log.error("state/code: " + se.getSQLState() + "/" + se.getErrorCode());
-        log.debug("      dump:", se);
-    }
-
-    /**
-     * Makes sure that <code>schemaObjectPrefix</code> does only consist of
-     * characters that are allowed in names on the target database. Illegal
-     * characters will be escaped as necessary.
-     *
-     * @throws Exception if an error occurs
-     */
-    protected void prepareSchemaObjectPrefix() throws Exception {
-        DatabaseMetaData metaData = con.getMetaData();
-        String legalChars = metaData.getExtraNameCharacters();
-        legalChars += "ABCDEFGHIJKLMNOPQRSTUVWXZY0123456789_";
-
-        String prefix = schemaObjectPrefix.toUpperCase();
-        StringBuffer escaped = new StringBuffer();
-        for (int i = 0; i < prefix.length(); i++) {
-            char c = prefix.charAt(i);
-            if (legalChars.indexOf(c) == -1) {
-                escaped.append("_x");
-                String hex = Integer.toHexString(c);
-                escaped.append("0000".toCharArray(), 0, 4 - hex.length());
-                escaped.append(hex);
-                escaped.append("_");
-            } else {
-                escaped.append(c);
-            }
-        }
-        schemaObjectPrefix = escaped.toString();
-    }
-
-    /**
-     * Checks if the required schema objects exist and creates them if they
-     * don't exist yet.
-     *
-     * @throws Exception if an error occurs
-     */
-    protected void checkSchema() throws Exception {
-        DatabaseMetaData metaData = con.getMetaData();
-        String tableName = schemaObjectPrefix + "NODE";
-        if (metaData.storesLowerCaseIdentifiers()) {
-            tableName = tableName.toLowerCase();
-        } else if (metaData.storesUpperCaseIdentifiers()) {
-            tableName = tableName.toUpperCase();
-        }
-
-        ResultSet rs = metaData.getTables(null, null, tableName, null);
-        boolean schemaExists;
-        try {
-            schemaExists = rs.next();
-        } finally {
-            rs.close();
-        }
-
-        if (!schemaExists) {
-            // read ddl from resources
-            InputStream in = getClass().getResourceAsStream(schema + ".ddl");
-            if (in == null) {
-                String msg = "Configuration error: unknown schema '" + schema + "'";
-                log.debug(msg);
-                throw new RepositoryException(msg);
-            }
-            BufferedReader reader = new BufferedReader(new InputStreamReader(in));
-            Statement stmt = con.createStatement();
-            try {
-                String sql = reader.readLine();
-                while (sql != null) {
-                    // replace prefix variable
-                    sql = Text.replace(sql, SCHEMA_OBJECT_PREFIX_VARIABLE, schemaObjectPrefix);
-                    // execute sql stmt
-                    stmt.executeUpdate(sql);
-                    // read next sql stmt
-                    sql = reader.readLine();
-                }
-                // commit the changes
-                con.commit();
-            } finally {
-                closeStream(in);
-                closeStatement(stmt);
-            }
-        }
+        Connection connection = DriverManager.getConnection(url, user, password);
+        return connection;
     }
 
-    //--------------------------------------------------------< inner classes >
-    class DbBLOBStore implements BLOBStore {
-        /**
-         * {@inheritDoc}
-         */
-        public String createId(PropertyId id, int index) {
-            // the blobId is a simple string concatenation of id plus index
-            StringBuffer sb = new StringBuffer();
-            sb.append(id.toString());
-            sb.append('[');
-            sb.append(index);
-            sb.append(']');
-            return sb.toString();
-        }
-
-        /**
-         * {@inheritDoc}
-         */
-        public InputStream get(String blobId) throws Exception {
-            PreparedStatement stmt = blobSelect;
-            synchronized(stmt) {
-                try {
-                    stmt.setString(1, blobId);
-                    stmt.execute();
-                    final ResultSet rs = stmt.getResultSet();
-                    if (!rs.next()) {
-                        closeResultSet(rs);
-                        throw new Exception("no such BLOB: " + blobId);
-                    }
-                    InputStream in = rs.getBinaryStream(1);
-                    if (in == null) {
-                        // some databases treat zero-length values as NULL;
-                        // return empty InputStream in such a case
-                        closeResultSet(rs);
-                        return new ByteArrayInputStream(new byte[0]);
-                    }
-
-                    /**
-                     * return an InputStream wrapper in order to
-                     * close the ResultSet when the stream is closed
-                     */
-                    return new FilterInputStream(in) {
-                        public void close() throws IOException {
-                            in.close();
-                            // now it's safe to close ResultSet
-                            closeResultSet(rs);
-                        }
-                    };
-                } finally {
-                    resetStatement(stmt);
-                }
-            }
-        }
-
-        /**
-         * {@inheritDoc}
-         */
-        public synchronized void put(String blobId, InputStream in, long size)
-                throws Exception {
-            PreparedStatement stmt = blobSelectExist;
-            try {
-                stmt.setString(1, blobId);
-                stmt.execute();
-                ResultSet rs = stmt.getResultSet();
-                // a BLOB exists if the result has at least one entry
-                boolean exists = rs.next();
-                resetStatement(stmt);
-                closeResultSet(rs);
-
-                stmt = (exists) ? blobUpdate : blobInsert;
-                stmt.setBinaryStream(1, in, (int) size);
-                stmt.setString(2, blobId);
-                stmt.executeUpdate();
-            } finally {
-                resetStatement(stmt);
-            }
-        }
-
-        /**
-         * {@inheritDoc}
-         */
-        public synchronized boolean remove(String blobId) throws Exception {
-            PreparedStatement stmt = blobDelete;
-            try {
-                stmt.setString(1, blobId);
-                return stmt.executeUpdate() == 1;
-            } finally {
-                resetStatement(stmt);
-            }
-        }
-    }
 }