/* The contents of this file are subject to the license and copyright terms
* detailed in the license directory at the root of the source tree (also
* available online at http://fedora-commons.org/license/).
*/
package org.fcrepo.server.journal.recoverylog;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Map;
import org.fcrepo.server.errors.ModuleInitializationException;
import org.fcrepo.server.journal.ServerInterface;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A basic implementation of RecoveryLog.
* <p>
* All entries are written to a log, which is flushed after each entry so the
* log will be up to date even if the server crashes.
*
* @author Jim Blake
*/
public class UnbufferedJournalRecoveryLog
extends JournalRecoveryLog {
private static final Logger logger =
LoggerFactory.getLogger(UnbufferedJournalRecoveryLog.class);
private final File logFile;
private final FileWriter writer;
private boolean open = true;
/**
* Get the name of the logfile from the server parameters and create the
* file.
*/
public UnbufferedJournalRecoveryLog(Map<String, String> parameters,
String role,
ServerInterface server)
throws ModuleInitializationException {
super(parameters, role, server);
try {
if (!parameters.containsKey(PARAMETER_RECOVERY_LOG_FILENAME)) {
throw new ModuleInitializationException("Parameter '"
+ PARAMETER_RECOVERY_LOG_FILENAME
+ "' is not set.",
role);
}
String fileName = parameters.get(PARAMETER_RECOVERY_LOG_FILENAME);
logFile = new File(fileName);
writer = new FileWriter(logFile);
super.logHeaderInfo(parameters);
} catch (IOException e) {
throw new ModuleInitializationException("Problem writing to the recovery log",
role,
e);
}
}
/**
* A request to log a message just writes it to the log file and flushes it
* (if shutdown has not been called).
*/
@Override
public synchronized void log(String message) {
try {
if (open) {
log(message, writer);
writer.flush();
}
} catch (IOException e) {
logger.error("Error writing journal log entry", e);
}
}
/**
* On the first call to this method, close the log file. Set the flag so no
* more logging calls will be accepted.
*/
@Override
public synchronized void shutdown() {
try {
if (open) {
open = false;
writer.close();
}
} catch (IOException e) {
logger.error("Error shutting down journal log", e);
}
}
@Override
public String toString() {
return super.toString() + ", logFile='" + logFile.getPath() + "'";
}
}