es.caib.sgtsic.ejb3.AbstractFacade.java Source code

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Here is the source code for es.caib.sgtsic.ejb3.AbstractFacade.java

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package es.caib.sgtsic.ejb3;

import java.lang.reflect.Field;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.persistence.EntityManager;
import javax.persistence.ManyToMany;
import javax.persistence.OneToMany;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 *
 * @author gdeignacio
 * @param <T>
 */
public abstract class AbstractFacade<T> {

    protected static Log log = LogFactory.getLog(AbstractFacade.class);

    private final Class<T> entityClass;

    /**
     *
     * @param entityClass
     */
    public AbstractFacade(Class<T> entityClass) {
        this.entityClass = entityClass;
    }

    protected abstract EntityManager getEntityManager();

    public void create(T entity) {
        getEntityManager().persist(entity);
    }

    public void edit(T entity) {
        getEntityManager().merge(entity);
    }

    public void remove(T entity) {
        getEntityManager().remove(getEntityManager().merge(entity));
    }

    public T find(Object id) {
        return getEntityManager().find(entityClass, id);
    }

    public List<T> findAll() {
        return getEntityManager().createQuery("select object(o) from " + entityClass.getSimpleName() + " as o")
                .getResultList();
    }

    public List<T> findRange(int[] range) {
        javax.persistence.Query q = getEntityManager()
                .createQuery("select object(o) from " + entityClass.getSimpleName() + " as o");
        q.setMaxResults(range[1] - range[0] + 1);
        q.setFirstResult(range[0]);
        return q.getResultList();
    }

    public int count() {
        return ((Long) getEntityManager()
                .createQuery("select count(o) from " + entityClass.getSimpleName() + " as o").getSingleResult())
                        .intValue();
    }

    private int childrenCount(Object id, Class entityChild, Class mappedBy) {

        log.debug("Entramos a childrenCount");
        log.debug("Entramos a childrenCount" + entityChild);
        log.debug("Entramos a childrenCount" + mappedBy);

        String namedQueryName = entityChild.getSimpleName() + ".findCountBy" + entityClass.getSimpleName();

        int count = ((Long) getEntityManager().createNamedQuery(namedQueryName)
                .setParameter("id" + mappedBy.getSimpleName(), id).getSingleResult()).intValue();

        log.debug("Entramos a childrenCount resultado" + count);

        return count;
    }

    public T wideFind(Object id) {

        boolean isBorrable = true;
        T item = this.find(id);

        if (item == null) {
            return item;
        }

        for (Field f : entityClass.getDeclaredFields()) {

            boolean hasToManyAnnotations = (f.isAnnotationPresent(OneToMany.class))
                    || (f.isAnnotationPresent(ManyToMany.class));

            if (hasToManyAnnotations) {

                try {
                    f.setAccessible(true);
                    isBorrable = isBorrable && ((List) f.get(item)).isEmpty();
                    f.setAccessible(false);
                } catch (IllegalArgumentException | IllegalAccessException ex) {
                    Logger.getLogger(AbstractFacade.class.getName()).log(Level.SEVERE, null, ex);
                }

            }
        }

        return item;
    }

    public boolean borrable(Object id) {

        T item = this.find(id);

        log.debug("Entramos a borrable " + item);

        if (item == null) {
            return false;
        }

        log.debug("Entramos a borrable con no false " + item);

        for (Field f : entityClass.getDeclaredFields()) {
            boolean hasToManyAnnotations = (f.isAnnotationPresent(OneToMany.class))
                    || (f.isAnnotationPresent(ManyToMany.class));
            if (hasToManyAnnotations) {

                Type type = f.getGenericType();
                ParameterizedType pt = (ParameterizedType) type;

                List<Type> arguments = Arrays.asList(pt.getActualTypeArguments());

                Class childEntityClass = null;

                for (Type argtype : arguments) {
                    childEntityClass = (Class) argtype;
                    break;
                }

                if (childEntityClass == null)
                    continue;

                if (this.childrenCount(id, childEntityClass, entityClass) > 0) {

                    log.debug("Cuenta positiva");

                    return false;
                }
            }
        }

        log.debug("Cuenta 0");

        return true;

    }

}