Tratamento de concorrencia usando hibernate

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package util;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import org.hibernate.HibernateException;
import org.hibernate.SessionFactory;

/**
 *
 * @author Deivid
 */
@WebFilter(filterName = "hibernateFilter",urlPatterns = "/*")
public class HibernateFilter implements Filter{

    private SessionFactory sf;
    
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        this.sf = HibernateUtil.getSessionFactory();
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        try {
            
            this.sf.getCurrentSession().beginTransaction();
            chain.doFilter(request, response);
            this.sf.getCurrentSession().getTransaction().commit();
            
        } catch (HibernateException | IOException | ServletException e) {
            try {
                if(this.sf.getCurrentSession().getTransaction().isActive()){
                this.sf.getCurrentSession().getTransaction().rollback();
                }
            } catch (HibernateException ee) {
            }
        }finally{
        
            this.sf.getCurrentSession().close();
        }
    }

    @Override
    public void destroy() {
        this.sf.close();
    }
    
}