/*
|
* CDDL HEADER START
|
*
|
* The contents of this file are subject to the terms of the
|
* Common Development and Distribution License, Version 1.0 only
|
* (the "License"). You may not use this file except in compliance
|
* with the License.
|
*
|
* You can obtain a copy of the license at
|
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
|
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
|
* See the License for the specific language governing permissions
|
* and limitations under the License.
|
*
|
* When distributing Covered Code, include this CDDL HEADER in each
|
* file and include the License file at
|
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
|
* add the following below this CDDL HEADER, with the fields enclosed
|
* by brackets "[]" replaced with your own identifying information:
|
* Portions Copyright [yyyy] [name of copyright owner]
|
*
|
* CDDL HEADER END
|
*
|
*
|
* Copyright 2009 Sun Microsystems, Inc.
|
* Portions Copyright 2011 ForgeRock AS
|
*/
|
package org.opends.server.replication.server;
|
import static org.opends.messages.ReplicationMessages.*;
|
import static org.opends.server.loggers.ErrorLogger.logError;
|
import static org.opends.server.loggers.debug.DebugLogger.getTracer;
|
import static org.opends.server.util.StaticUtils.decodeUTF8;
|
import static org.opends.server.util.StaticUtils.stackTraceToSingleLineString;
|
|
import java.io.UnsupportedEncodingException;
|
import java.util.concurrent.locks.ReentrantReadWriteLock;
|
|
import org.opends.messages.MessageBuilder;
|
import org.opends.server.loggers.debug.DebugTracer;
|
import org.opends.server.replication.common.ChangeNumber;
|
import org.opends.server.types.DebugLogLevel;
|
|
import com.sleepycat.je.Cursor;
|
import com.sleepycat.je.Database;
|
import com.sleepycat.je.DatabaseEntry;
|
import com.sleepycat.je.DatabaseException;
|
import com.sleepycat.je.LockConflictException;
|
import com.sleepycat.je.LockMode;
|
import com.sleepycat.je.OperationStatus;
|
import com.sleepycat.je.Transaction;
|
|
/**
|
* This class implements the interface between the underlying database
|
* and the dbHandler class.
|
* This is the only class that should have code using the BDB interfaces.
|
*/
|
public class DraftCNDB
|
{
|
private static final DebugTracer TRACER = getTracer();
|
private Database db = null;
|
private ReplicationDbEnv dbenv = null;
|
private ReplicationServer replicationServer;
|
|
// The maximum number of retries in case of DatabaseDeadlock Exception.
|
private static final int DEADLOCK_RETRIES = 10;
|
|
// The lock used to provide exclusive access to the thread that
|
// close the db (shutdown or clear).
|
private ReentrantReadWriteLock dbCloseLock;
|
|
/**
|
* Creates a new database or open existing database that will be used
|
* to store and retrieve changes from an LDAP server.
|
* @param replicationServer The ReplicationServer that needs to be shutdown.
|
* @param dbenv The Db environment to use to create the db.
|
* @throws DatabaseException If a database problem happened.
|
*/
|
public DraftCNDB(
|
ReplicationServer replicationServer,
|
ReplicationDbEnv dbenv)
|
throws DatabaseException
|
{
|
this.dbenv = dbenv;
|
this.replicationServer = replicationServer;
|
|
// Get or create the associated ReplicationServerDomain and Db.
|
db = dbenv.getOrCreateDraftCNDb();
|
|
dbCloseLock = new ReentrantReadWriteLock(true);
|
}
|
|
/**
|
* Add an entry to the database.
|
* @param draftCN the provided draftCN.
|
*
|
* @param value the provided value to be stored associated
|
* with this draftCN.
|
* @param domainBaseDN the provided domainBaseDn to be stored associated
|
* with this draftCN.
|
* @param changeNumber the provided replication change number to be
|
* stored associated with this draftCN.
|
*/
|
public void addEntry(int draftCN, String value, String domainBaseDN,
|
ChangeNumber changeNumber)
|
{
|
Transaction txn = null;
|
try
|
{
|
int tries = 0;
|
boolean done = false;
|
|
// The database can return a Deadlock Exception if several threads are
|
// accessing the database at the same time. This Exception is a
|
// transient state, when it happens the transaction is aborted and
|
// the operation is attempted again up to DEADLOCK_RETRIES times.
|
while ((tries++ < DEADLOCK_RETRIES) && (!done))
|
{
|
dbCloseLock.readLock().lock();
|
try
|
{
|
txn = dbenv.beginTransaction();
|
|
DatabaseEntry key = new ReplicationDraftCNKey(draftCN);
|
DatabaseEntry data = new DraftCNData(draftCN,
|
value, domainBaseDN, changeNumber);
|
db.put(txn, key, data);
|
txn.commitWriteNoSync();
|
txn = null;
|
done = true;
|
}
|
catch (LockConflictException e)
|
{
|
// Try again.
|
}
|
finally
|
{
|
if (txn != null)
|
{
|
// No effect if txn has committed.
|
txn.abort();
|
txn = null;
|
}
|
dbCloseLock.readLock().unlock();
|
}
|
}
|
if (!done)
|
{
|
// Could not write to the DB after DEADLOCK_RETRIES tries.
|
// This ReplicationServer is not reliable and will be shutdown.
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
}
|
}
|
catch (DatabaseException e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
}
|
catch (UnsupportedEncodingException e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_UNSUPPORTED_UTF8_ENCODING.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
}
|
}
|
|
/**
|
* Shutdown the database.
|
*/
|
public void shutdown()
|
{
|
try
|
{
|
dbCloseLock.writeLock().lock();
|
try
|
{
|
db.close();
|
}
|
finally
|
{
|
dbCloseLock.writeLock().unlock();
|
}
|
}
|
catch (DatabaseException e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(NOTE_EXCEPTION_CLOSING_DATABASE.get(this.toString()));
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
}
|
}
|
|
/**
|
* Create a cursor that can be used to search or iterate on this DB.
|
*
|
* @param draftCN The draftCN from which the cursor must start.
|
* @throws DatabaseException If a database error prevented the cursor
|
* creation.
|
* @throws Exception if the ReplServerDBCursor creation failed.
|
* @return The ReplServerDBCursor.
|
*/
|
public DraftCNDBCursor openReadCursor(int draftCN)
|
throws DatabaseException, Exception
|
{
|
return new DraftCNDBCursor(draftCN);
|
}
|
|
/**
|
* Create a cursor that can be used to delete some record from this
|
* ReplicationServer database.
|
*
|
* @throws DatabaseException If a database error prevented the cursor
|
* creation.
|
* @throws Exception if the ReplServerDBCursor creation failed.
|
*
|
* @return The ReplServerDBCursor.
|
*/
|
public DraftCNDBCursor openDeleteCursor()
|
throws DatabaseException, Exception
|
{
|
return new DraftCNDBCursor();
|
}
|
|
private void closeLockedCursor(Cursor cursor)
|
throws DatabaseException
|
{
|
try
|
{
|
if (cursor != null)
|
cursor.close();
|
}
|
finally
|
{
|
dbCloseLock.readLock().unlock();
|
}
|
}
|
|
/**
|
* Read the first Change from the database, 0 when none.
|
* @return the first draftCN.
|
*/
|
public int readFirstDraftCN()
|
{
|
Cursor cursor = null;
|
String str = null;
|
|
try
|
{
|
dbCloseLock.readLock().lock();
|
try
|
{
|
cursor = db.openCursor(null, null);
|
DatabaseEntry key = new DatabaseEntry();
|
DatabaseEntry entry = new DatabaseEntry();
|
OperationStatus status = cursor.getFirst(key, entry, LockMode.DEFAULT);
|
if (status != OperationStatus.SUCCESS)
|
{
|
/* database is empty */
|
return 0;
|
}
|
str = decodeUTF8(key.getData());
|
int sn = new Integer(str);
|
return sn;
|
}
|
finally
|
{
|
closeLockedCursor(cursor);
|
}
|
}
|
catch (DatabaseException e)
|
{
|
/* database is faulty */
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
return 0;
|
}
|
catch (Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
return 0;
|
}
|
}
|
|
/**
|
* Return the record count.
|
* @return the record count.
|
*/
|
public long count()
|
{
|
try
|
{
|
return db.count();
|
}
|
catch(Exception e)
|
{
|
TRACER.debugCaught(DebugLogLevel.ERROR, e);
|
}
|
return 0L;
|
}
|
|
/**
|
* Read the last draftCN from the database.
|
* @return the last draftCN.
|
*/
|
public int readLastDraftCN()
|
{
|
Cursor cursor = null;
|
String str = null;
|
|
try
|
{
|
dbCloseLock.readLock().lock();
|
try
|
{
|
cursor = db.openCursor(null, null);
|
DatabaseEntry key = new DatabaseEntry();
|
DatabaseEntry entry = new DatabaseEntry();
|
OperationStatus status = cursor.getLast(key, entry, LockMode.DEFAULT);
|
if (status != OperationStatus.SUCCESS)
|
{
|
/* database is empty */
|
return 0;
|
}
|
str = decodeUTF8(key.getData());
|
int sn = new Integer(str);
|
return sn;
|
}
|
finally
|
{
|
closeLockedCursor(cursor);
|
}
|
}
|
catch (DatabaseException e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
replicationServer.shutdown();
|
return 0;
|
}
|
catch (Exception e)
|
{
|
replicationServer.shutdown();
|
return 0;
|
}
|
}
|
|
/**
|
* {@inheritDoc}
|
*/
|
@Override
|
public String toString()
|
{
|
return "DraftCNDB";
|
}
|
|
/**
|
* This Class implements a cursor that can be used to browse the database.
|
*/
|
public class DraftCNDBCursor
|
{
|
private final Cursor cursor;
|
|
// The transaction that will protect the actions done with the cursor
|
// Will be let null for a read cursor
|
// Will be set non null for a write cursor
|
private final Transaction txn;
|
private final DatabaseEntry key;
|
private final DatabaseEntry entry;
|
|
private boolean isClosed = false;
|
|
|
|
/**
|
* Creates a cursor that can be used for browsing the db.
|
*
|
* @param startingDraftCN
|
* the draftCN from which the cursor must start.
|
* @throws Exception
|
* when the startingDraftCN does not exist.
|
*/
|
private DraftCNDBCursor(int startingDraftCN) throws Exception
|
{
|
// For consistency with other constructor, we'll use a local here,
|
// even though it's always null.
|
final Transaction localTxn = null;
|
Cursor localCursor = null;
|
|
this.key = new ReplicationDraftCNKey(startingDraftCN);
|
this.entry = new DatabaseEntry();
|
|
// Take the lock. From now on, whatever error that happen in the life
|
// of this cursor should end by unlocking that lock. We must also
|
// unlock it when throwing an exception.
|
dbCloseLock.readLock().lock();
|
|
try
|
{
|
localCursor = db.openCursor(localTxn, null);
|
if (startingDraftCN >= 0)
|
{
|
if (localCursor.getSearchKey(
|
key, entry, LockMode.DEFAULT) != OperationStatus.SUCCESS)
|
{
|
// We could not move the cursor to the expected startingChangeNumber
|
if (localCursor.getSearchKeyRange(key, entry,
|
LockMode.DEFAULT) != OperationStatus.SUCCESS)
|
{
|
// We could not even move the cursor closed to it => failure
|
throw new Exception("ChangeLog Draft Change Number "
|
+ startingDraftCN + " is not available");
|
}
|
else
|
{
|
// We can move close to the startingChangeNumber.
|
// Let's create a cursor from that point.
|
DatabaseEntry key = new DatabaseEntry();
|
DatabaseEntry data = new DatabaseEntry();
|
if (localCursor.getPrev(
|
key, data, LockMode.DEFAULT) != OperationStatus.SUCCESS)
|
{
|
localCursor.close();
|
localCursor = db.openCursor(localTxn, null);
|
}
|
}
|
}
|
}
|
|
this.txn = localTxn;
|
this.cursor = localCursor;
|
}
|
catch (Exception e)
|
{
|
// Unlocking is required before throwing any exception
|
closeLockedCursor(localCursor);
|
throw e;
|
}
|
}
|
|
|
|
private DraftCNDBCursor() throws Exception
|
{
|
Transaction localTxn = null;
|
Cursor localCursor = null;
|
|
this.key = new DatabaseEntry();
|
this.entry = new DatabaseEntry();
|
|
// We'll go on only if no close or no clear is running
|
dbCloseLock.readLock().lock();
|
try
|
{
|
// Create the transaction that will protect whatever done with this
|
// write cursor.
|
localTxn = dbenv.beginTransaction();
|
localCursor = db.openCursor(localTxn, null);
|
|
this.txn = localTxn;
|
this.cursor = localCursor;
|
}
|
catch (Exception e)
|
{
|
TRACER.debugCaught(DebugLogLevel.ERROR, e);
|
|
try
|
{
|
closeLockedCursor(localCursor);
|
}
|
catch (DatabaseException ignored)
|
{
|
// Ignore.
|
TRACER.debugCaught(DebugLogLevel.ERROR, ignored);
|
}
|
|
if (localTxn != null)
|
{
|
try
|
{
|
localTxn.abort();
|
}
|
catch (DatabaseException ignored)
|
{
|
// Ignore.
|
TRACER.debugCaught(DebugLogLevel.ERROR, ignored);
|
}
|
}
|
throw e;
|
}
|
}
|
|
/**
|
* Close the ReplicationServer Cursor.
|
*/
|
public void close()
|
{
|
synchronized (this)
|
{
|
if (isClosed)
|
{
|
return;
|
}
|
isClosed = true;
|
}
|
|
boolean closeHasFailed = false;
|
|
try
|
{
|
closeLockedCursor(cursor);
|
}
|
catch (Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
closeHasFailed = true;
|
}
|
|
if (txn != null)
|
{
|
try
|
{
|
txn.commit();
|
}
|
catch (Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
closeHasFailed = true;
|
}
|
}
|
|
if (closeHasFailed)
|
{
|
replicationServer.shutdown();
|
}
|
}
|
|
/**
|
* Abort the Cursor after a Deadlock Exception.
|
* This method catch and ignore the DeadlockException because
|
* this must be done when aborting a cursor after a DeadlockException
|
* (per the Cursor documentation).
|
* This should not be used in any other case.
|
*/
|
public void abort()
|
{
|
synchronized (this)
|
{
|
if (isClosed)
|
{
|
return;
|
}
|
isClosed = true;
|
}
|
|
boolean closeHasFailed = false;
|
|
try
|
{
|
closeLockedCursor(cursor);
|
}
|
catch (LockConflictException e)
|
{
|
// The DB documentation states that a DeadlockException
|
// on the close method of a cursor that is aborting should
|
// be ignored.
|
}
|
catch (Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
closeHasFailed = true;
|
}
|
|
if (txn != null)
|
{
|
try
|
{
|
txn.abort();
|
}
|
catch (Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_CHANGELOG_SHUTDOWN_DATABASE_ERROR.get());
|
mb.append(stackTraceToSingleLineString(e));
|
logError(mb.toMessage());
|
closeHasFailed = true;
|
}
|
}
|
|
if (closeHasFailed)
|
{
|
replicationServer.shutdown();
|
}
|
}
|
|
/**
|
* Getter for the value field of the current cursor.
|
* @return The current value field.
|
*/
|
public String currentValue()
|
{
|
try
|
{
|
OperationStatus status =
|
cursor.getCurrent(key, entry, LockMode.DEFAULT);
|
|
if (status != OperationStatus.SUCCESS)
|
{
|
return null;
|
}
|
DraftCNData seqnumData = new DraftCNData(entry.getData());
|
return seqnumData.getValue();
|
}
|
catch(Exception e)
|
{
|
TRACER.debugCaught(DebugLogLevel.ERROR, e);
|
}
|
return null;
|
}
|
|
/**
|
* Getter for the serviceID field of the current cursor.
|
* @return The current serviceID.
|
*/
|
public String currentServiceID()
|
{
|
try
|
{
|
OperationStatus status =
|
cursor.getCurrent(key, entry, LockMode.DEFAULT);
|
|
if (status != OperationStatus.SUCCESS)
|
{
|
return null;
|
}
|
DraftCNData seqnumData = new DraftCNData(entry.getData());
|
return seqnumData.getServiceID();
|
}
|
catch(Exception e)
|
{
|
TRACER.debugCaught(DebugLogLevel.ERROR, e);
|
}
|
return null;
|
}
|
|
/**
|
* Returns the replication changeNumber associated with the current key.
|
* @return the replication changeNumber
|
*/
|
public ChangeNumber currentChangeNumber()
|
{
|
try
|
{
|
OperationStatus status =
|
cursor.getCurrent(key, entry, LockMode.DEFAULT);
|
|
if (status != OperationStatus.SUCCESS)
|
{
|
return null;
|
}
|
DraftCNData seqnumData =
|
new DraftCNData(entry.getData());
|
return seqnumData.getChangeNumber();
|
}
|
catch(Exception e)
|
{
|
TRACER.debugCaught(DebugLogLevel.ERROR, e);
|
}
|
return null;
|
}
|
|
/**
|
* Go to the next record on the cursor.
|
* @return the next record on this cursor.
|
* @throws DatabaseException a.
|
*/
|
public boolean next() throws DatabaseException
|
{
|
OperationStatus status = cursor.getNext(key, entry, LockMode.DEFAULT);
|
if (status != OperationStatus.SUCCESS)
|
{
|
return false;
|
}
|
return true;
|
}
|
|
/**
|
* Delete the record at the current cursor position.
|
*
|
* @throws DatabaseException In case of database problem.
|
*/
|
public void delete() throws DatabaseException
|
{
|
cursor.delete();
|
}
|
|
/**
|
* Returns the current key associated with this cursor.
|
*
|
* @return The current key associated with this cursor.
|
*/
|
public DatabaseEntry getKey()
|
{
|
return key;
|
}
|
}
|
|
/**
|
* Clears this change DB from the changes it contains.
|
*
|
* @throws Exception Throws an exception it occurs.
|
* @throws DatabaseException Throws a DatabaseException when it occurs.
|
*/
|
public void clear() throws Exception, DatabaseException
|
{
|
// The coming users will be blocked until the clear is done
|
dbCloseLock.writeLock().lock();
|
try
|
{
|
String dbName = db.getDatabaseName();
|
|
// Closing is requested by the Berkeley DB before truncate
|
db.close();
|
|
// Clears the changes
|
dbenv.clearDb(dbName);
|
|
// RE-create the db
|
db = dbenv.getOrCreateDraftCNDb();
|
}
|
catch(Exception e)
|
{
|
MessageBuilder mb = new MessageBuilder();
|
mb.append(ERR_ERROR_CLEARING_DB.get(this.toString(),
|
e.getMessage() + " " +
|
stackTraceToSingleLineString(e)));
|
logError(mb.toMessage());
|
}
|
finally
|
{
|
// Relax the waiting users
|
dbCloseLock.writeLock().unlock();
|
}
|
}
|
}
|
