private Connection getSqlConnection() throws LpException {
try {
return DriverManager.getConnection(
configuration.getVirtuosoUrl(), configuration.getUsername(), configuration.getPassword());
} catch (SQLException ex) {
throw exceptionFactory.failure("Can't create sql connection.", ex);
}
}
private void startLoading() throws LpException {
// Start loading.
Connection loaderConnection = null;
try {
loaderConnection = getSqlConnection();
try (Statement statementRun = loaderConnection.createStatement()) {
final ResultSet resultSetRun = statementRun.executeQuery("rdf_loader_run()");
resultSetRun.close();
}
} catch (SQLException ex) {
throw exceptionFactory.failure("Can't start loading.", ex);
} finally {
try {
if (loaderConnection != null) {
loaderConnection.close();
}
} catch (SQLException ex) {
LOG.warn("Can't close SQL connection.", ex);
}
}
}
@Override
public void execute() throws LpException {
// Create remote repository.
final VirtuosoRepository virtuosoRepository =
new VirtuosoRepository(
configuration.getVirtuosoUrl(),
configuration.getUsername(),
configuration.getPassword());
try {
virtuosoRepository.initialize();
} catch (RepositoryException ex) {
throw exceptionFactory.failure("Can't connect to Virtuoso repository.", ex);
}
cleanUp.addAction(
() -> {
try {
virtuosoRepository.shutDown();
} catch (RepositoryException ex) {
LOG.warn("Can't close repository.", ex);
}
});
// Delete data if set.
if (configuration.isClearDestinationGraph()) {
RepositoryConnection repositoryConnection = virtuosoRepository.getConnection();
try {
final Update update =
repositoryConnection.prepareUpdate(
QueryLanguage.SPARQL, getClearQuery(configuration.getTargetGraph()));
update.execute();
} finally {
try {
repositoryConnection.close();
} catch (RepositoryException ex) {
LOG.warn("Can't close connection.", ex);
}
}
}
final Connection connectionForInit = getSqlConnection();
// Insert data to load table.
try (PreparedStatement statementLdDir = connectionForInit.prepareStatement(SQL_LD_DIR)) {
statementLdDir.setString(1, configuration.getLoadDirectoryPath());
statementLdDir.setString(2, configuration.getLoadFileName());
statementLdDir.setString(3, configuration.getTargetGraph());
// Execute.
final ResultSet resultSetLdDir = statementLdDir.executeQuery();
resultSetLdDir.close();
} catch (SQLException ex) {
throw exceptionFactory.failure("Can't execute ld_dir query.", ex);
}
// Check number of files to load.
final int filesToLoad;
try (PreparedStatement statementStatusCountProcessing =
connectionForInit.prepareStatement(SQL_QUERY_WAITING)) {
statementStatusCountProcessing.setString(1, configuration.getLoadDirectoryPath() + "%");
try (ResultSet resultSetProcessing = statementStatusCountProcessing.executeQuery()) {
resultSetProcessing.next();
filesToLoad = resultSetProcessing.getInt(1);
}
} catch (SQLException ex) {
throw exceptionFactory.failure("Can't query load_list table.", ex);
} finally {
// Here we can close the connection.
try {
connectionForInit.close();
} catch (SQLException ex) {
LOG.warn("Can't close SQL connection.", ex);
}
}
LOG.info("Load list holds {} files to process", filesToLoad);
if (filesToLoad == 0) {
LOG.info("Nothing to do. Stopping.");
return;
}
// Start loading, we use only a single thread call here.
startLoading();
// Check for status - periodic and final.
while (true) {
final Connection connectionForStatusCheck = getSqlConnection();
try (PreparedStatement statement =
connectionForStatusCheck.prepareStatement(SQL_QUERY_FINISHED)) {
statement.setString(1, configuration.getLoadDirectoryPath() + "%");
try (ResultSet resultSetDoneLoop = statement.executeQuery()) {
resultSetDoneLoop.next();
int filesLoaded = resultSetDoneLoop.getInt(1);
LOG.info("Processing {}/{} files", filesLoaded, filesToLoad);
if (filesLoaded == filesToLoad) {
break;
}
}
} catch (SQLException ex) {
LOG.warn("Can't query status.", ex);
} finally {
try {
connectionForStatusCheck.close();
} catch (SQLException ex) {
LOG.warn("Can't close SQL connection.", ex);
}
}
// Wait before next check.
try {
Thread.sleep(configuration.getStatusUpdateInterval() * 1000);
} catch (InterruptedException ex) {
// Do nothing here.
}
}
if (configuration.isClearLoadList()) {
final Connection connectionForDelete = getSqlConnection();
// Delete from loading table - made optional.
try (PreparedStatement delete = connectionForDelete.prepareStatement(SQL_DELETE_LOAD_LIST)) {
delete.setString(1, configuration.getLoadDirectoryPath() + "%");
delete.executeUpdate();
} catch (SQLException ex) {
} finally {
try {
connectionForDelete.close();
} catch (SQLException ex) {
LOG.warn("Can't close SQL connection.", ex);
}
}
}
}