package net.sourceforge.fenixedu.persistenceTier;

import org.apache.ojb.broker.PersistenceBroker;

import pt.ist.fenixWebFramework.services.ServiceManager;
import pt.ist.fenixframework.pstm.FenixCache;
import pt.ist.fenixframework.pstm.Transaction;
import pt.utl.ist.berserk.storage.ITransactionBroker;
import pt.utl.ist.berserk.storage.exceptions.StorageException;

import com.linkare.commons.metainfo.Linkare;

public class SuportePersistenteOJB implements ISuportePersistente, ITransactionBroker {
    private static SuportePersistenteOJB _instance = null;

    public static synchronized SuportePersistenteOJB getInstance() {
	if (_instance == null) {
	    _instance = new SuportePersistenteOJB();
	}
	return _instance;
    }

    /** Creates a new instance of SuportePersistenteOJB */
    private SuportePersistenteOJB() {
    }

    public void iniciarTransaccao() {
	// commit any current transaction
	if (Transaction.current() != null) {
	    Transaction.commit();
	}
	Transaction.begin();
    }

    public void confirmarTransaccao() {
	Transaction.checkpoint();
	Transaction.currentFenixTransaction().setReadOnly();
    }

    public void cancelarTransaccao() {
	Transaction.abort();
	Transaction.begin();
	Transaction.currentFenixTransaction().setReadOnly();
    }

    public void beginTransaction() {
	if (ServiceManager.isInsideBerserkService())
	    this.iniciarTransaccao();
    }

    public void commitTransaction() {
	if (ServiceManager.isInsideBerserkService())
	    this.confirmarTransaccao();
    }

    public void abortTransaction() throws StorageException {
	if (ServiceManager.isInsideBerserkService())
	    this.cancelarTransaccao();
    }

    public void lockRead(java.util.List list) throws StorageException {
    }

    public void lockRead(Object obj) throws StorageException {
    }

    public void lockWrite(Object obj) throws StorageException {
    }

    @Linkare(author = "José Pereira")
    public static PersistenceBroker getCurrentPersistenceBroker() {
	return Transaction.getOJBBroker();
    }

    @Linkare(author = "José Pereira")
    public void clearCache() {
	getCurrentPersistenceBroker().clearCache();
    }

    @Linkare(author = "José Pereira")
    public Integer getNumberCachedItems() {
	return Integer.valueOf(FenixCache.getNumberOfCachedItems());
    }
}