/**
* Copyright (C) 2000-2010 Atomikos <info@atomikos.com>
*
* This code ("Atomikos TransactionsEssentials"), by itself,
* is being distributed under the
* Apache License, Version 2.0 ("License"), a copy of which may be found at
* http://www.atomikos.com/licenses/apache-license-2.0.txt .
* You may not use this file except in compliance with the License.
*
* While the License grants certain patent license rights,
* those patent license rights only extend to the use of
* Atomikos TransactionsEssentials by itself.
*
* This code (Atomikos TransactionsEssentials) contains certain interfaces
* in package (namespace) com.atomikos.icatch
* (including com.atomikos.icatch.Participant) which, if implemented, may
* infringe one or more patents held by Atomikos.
* It should be appreciated that you may NOT implement such interfaces;
* licensing to implement these interfaces must be obtained separately from Atomikos.
*
* 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.
*/
package com.atomikos.persistence.imp;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamException;
import java.io.StreamCorruptedException;
import java.util.Enumeration;
import java.util.Stack;
import java.util.Vector;
import com.atomikos.logging.Logger;
import com.atomikos.logging.LoggerFactory;
import com.atomikos.persistence.LogException;
import com.atomikos.persistence.LogStream;
import com.atomikos.util.VersionedFile;
/**
* A file implementation of a LogStream.
*/
public class FileLogStream implements LogStream
{
private static final Logger LOGGER = LoggerFactory.createLogger(FileLogStream.class);
private FileOutputStream output_;
// keeps track of the latest output stream returned
// from writeCheckpoint, so that it can be closed ( invalidated )
// if necessary.
private ObjectOutputStream ooutput_;
private boolean simulateCrash_;
// for testing
private boolean corrupt_;
// true if checkpoint; second call of recover
// not allowed, otherwise suffix_ will be wrong
// especially since checkpoint failed.
private VersionedFile file_;
public FileLogStream ( String baseDir , String baseName )
throws IOException
{
file_ = new VersionedFile ( baseDir , baseName , ".log" );
simulateCrash_ = false;
corrupt_ = false;
}
private void closeOutput () throws LogException
{
Stack errors = new Stack ();
// try to close the previous output stream, if any.
try {
if ( file_ != null ) {
file_.close();
if(LOGGER.isInfoEnabled()){
LOGGER.logInfo("Logfile closed: " + file_.getCurrentVersionFileName());
}
}
output_ = null;
ooutput_ = null;
} catch ( IOException e ) {
errors = new Stack ();
throw new LogException ( "Error closing previous output", errors );
}
}
/**
* Makes write checkpoint crash before old file delete.
*
* For debugging only.
*/
void setCrashMode ()
{
simulateCrash_ = true;
}
public synchronized Vector recover () throws LogException
{
if ( corrupt_ )
throw new LogException ( "Instance might be corrupted" );
Stack errors = new Stack ();
Vector ret = new Vector ();
InputStream in = null;
try {
FileInputStream f = file_.openLastValidVersionForReading();
in = f;
ObjectInputStream ins = new ObjectInputStream ( in );
int count = 0;
if(LOGGER.isInfoEnabled()){
LOGGER.logInfo("Starting read of logfile " + file_.getCurrentVersionFileName());
}
while ( in.available () > 0 ) {
// if crashed, then unproper closing might cause endless blocking!
// therefore, we check if avaible first.
count++;
Object nxt = ins.readObject ();
ret.addElement ( nxt );
if ( count % 10 == 0 ) {
LOGGER.logInfo(".");
}
}
LOGGER.logInfo("Done read of logfile");
} catch ( java.io.EOFException unexpectedEOF ) {
LOGGER.logDebug("Unexpected EOF - logfile not closed properly last time?" , unexpectedEOF);
// merely return what was read so far...
} catch ( StreamCorruptedException unexpectedEOF ) {
LOGGER.logDebug("Unexpected EOF - logfile not closed properly last time?" , unexpectedEOF);
// merely return what was read so far...
} catch ( ObjectStreamException unexpectedEOF ) {
LOGGER.logDebug("Unexpected EOF - logfile not closed properly last time?" , unexpectedEOF);
// merely return what was read so far...
} catch ( FileNotFoundException firstStart ) {
// the file could not be opened for reading;
// merely return the default empty vector
} catch ( Exception e ) {
String msg = "Error in recover";
LOGGER.logWarning(msg,e);
e.printStackTrace ();
errors.push ( e );
throw new LogException ( msg , errors );
} finally {
try {
if ( in != null )
in.close ();
} catch ( IOException io ) {
errors.push ( io );
throw new LogException ( "Error in recover", errors );
}
}
return ret;
}
public synchronized void writeCheckpoint ( Enumeration elements )
throws LogException
{
Stack errors = new Stack ();
// first, make sure that any pending output stream handles
// in the client are invalidated
closeOutput ();
try {
// open the new output file
// NOTE: after restart, any previous and failed checkpoint files
// will be overwritten here. That is perfectly OK.
output_ = file_.openNewVersionForWriting();
ooutput_ = new ObjectOutputStream ( output_ );
while ( elements != null && elements.hasMoreElements () ) {
Object next = elements.nextElement ();
ooutput_.writeObject ( next );
}
ooutput_.flush ();
output_.flush ();
output_.getFD ().sync ();
// NOTE: we do NOT close the object output, since the client
// will probably want to write more!
// Thus, we return the open stream to the client.
// Any closing will be done later, during cleanup if necessary.
if ( simulateCrash_ ) {
corrupt_ = true;
throw new LogException ( "Old file could not be deleted" );
}
try {
file_.discardBackupVersion();
} catch ( IOException errorOnDelete ) {
corrupt_ = true;
// should restart
throw new LogException ( "Old file could not be deleted" );
}
} catch ( Exception e ) {
errors.push ( e );
throw new LogException ( "Error during checkpointing", errors );
}
}
public synchronized void flushObject ( Object o, boolean shouldSync ) throws LogException
{
if ( ooutput_ == null )
throw new LogException ( "Not Initialized or already closed" );
try {
ooutput_.writeObject ( o );
output_.flush ();
ooutput_.flush ();
if (shouldSync) output_.getFD ().sync ();
} catch ( IOException e ) {
Stack errors = new Stack ();
throw new LogException ( e.getMessage (), errors );
}
}
public synchronized void close () throws LogException
{
closeOutput ();
}
public void finalize () throws Throwable
{
try {
close ();
} finally {
super.finalize ();
}
}
public long getSize() throws LogException
{
return file_.getSize();
}
}