/**
* List the justifications for the triple with the id given as argument. For informational
* purposes.
*
* @param tripleId
* @return
* @throws SailException
*/
public CloseableIteration<Justification, SailException> justify(long tripleId)
throws SailException {
try {
final KiWiReasoningConnection connection = persistence.getConnection();
return new ExceptionConvertingIteration<Justification, SailException>(
connection.listJustificationsForTriple(tripleId)) {
/**
* Converts an exception from the underlying iteration to an exception of type <tt>X</tt>.
*/
@Override
protected SailException convert(Exception e) {
return new SailException(e);
}
@Override
protected void handleClose() throws SailException {
super.handleClose();
try {
connection.commit();
connection.close();
} catch (SQLException ex) {
throw new SailException("database error while committing/closing connection");
}
}
};
} catch (SQLException ex) {
throw new SailException("cannot list programs in database", ex);
}
}
/**
* Return the program with the given name. In case the program does not exist, the method will
* return null.
*
* @param name the unique name of the program to retrieve
* @return the parsed program, or null in case a program with the given name does not exist
* @throws SailException in case an error occurs
*/
public Program getProgram(String name) throws SailException {
try {
KiWiReasoningConnection connection = persistence.getConnection();
try {
// should not throw an exception and the program should have a database ID afterwards
Program p = connection.loadProgram(name);
connection.commit();
return p;
} finally {
connection.close();
}
} catch (SQLException ex) {
throw new SailException("cannot load program from database", ex);
}
}
/**
* Remove the program with the given name. This method will first remove the program from the
* database and then inform the reasoning engine to run cleanups.
*
* <p>If a program with this name does not exist, does nothing
*
* @param name the unique name of the program to remove
* @throws SailException
*/
public void deleteProgram(String name) throws SailException {
try {
KiWiReasoningConnection connection = persistence.getConnection();
try {
Program p = connection.loadProgram(name);
connection.deleteProgram(p);
connection.commit();
} finally {
connection.close();
}
} catch (SQLException ex) {
throw new SailException("cannot load program from database", ex);
}
engine.loadPrograms();
engine.notifyRemoveRules();
}
/**
* Update the program given as argument. This method will first calculate the difference between
* the previous version of the program and the new version of the program. It then updates the
* program in the database and notifies the engine of all removed and added rules.
*
* @param program the updated version of the program
* @throws SailException in case a database error occurs
*/
public void updateProgram(Program program) throws SailException {
Set<Rule> added = new HashSet<Rule>();
Set<Rule> removed = new HashSet<Rule>();
try {
KiWiReasoningConnection connection = persistence.getConnection();
try {
// load old version of program and calculate difference
Program old = connection.loadProgram(program.getName());
if (old != null) {
for (Rule r : old.getRules()) {
if (!program.getRules().contains(r)) {
removed.add(r);
}
}
for (Rule r : program.getRules()) {
if (!old.getRules().contains(r)) {
added.add(r);
}
}
}
// store program in the database
connection.updateProgram(program);
connection.commit();
} finally {
connection.close();
}
} catch (SQLException ex) {
throw new SailException("cannot store program in database", ex);
}
engine.loadPrograms();
// if rules have been removed, clean up
if (removed.size() > 0) {
engine.notifyRemoveRules();
}
// now add all added rules to the reasoner
for (Rule rule : added) {
engine.notifyAddRule(rule);
}
}
/**
* Add a program to the reasoner. The program is persisted to the database and the reasoning
* engine is notified of the added rules and immediately calculates the inferences. Inferencing in
* this case is synchronous, so the method only returns when the first round of reasoning is
* completed for all added rules.
*
* <p>If a program with this name already exists, a SailException is thrown. To update existing
* programs, please use updateProgram().
*
* @param program the program data in KWRL syntax
* @throws SailException in case the program already exists
*/
public void addProgram(Program program) throws SailException {
// store program in the database
try {
KiWiReasoningConnection connection = persistence.getConnection();
try {
// should not throw an exception and the program should have a database ID afterwards
connection.storeProgram(program);
connection.commit();
} finally {
connection.close();
}
} catch (SQLException ex) {
throw new SailException("cannot store program in database", ex);
}
engine.loadPrograms();
// now add all added rules to the reasoner
for (Rule rule : program.getRules()) {
engine.notifyAddRule(rule);
}
}
@Override
public void initialize() throws SailException {
synchronized (this) {
if (!initialized) {
super.initialize();
KiWiStore store = getBaseStore();
try {
persistence = new KiWiReasoningPersistence(store.getPersistence(), getValueFactory());
persistence.initDatabase();
engine = new ReasoningEngine(persistence, this, config);
addTransactionListener(engine);
initialized = true;
} catch (SQLException e) {
log.error("error initializing reasoning database", e);
throw new SailException("error initializing reasoning database", e);
}
}
}
}
