hr.diskobolos.persistence.impl.ADaoPersistenceImpl.java Source code

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Here is the source code for hr.diskobolos.persistence.impl.ADaoPersistenceImpl.java

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package hr.diskobolos.persistence.impl;

import hr.diskobolos.model.IIdentifier;
import hr.diskobolos.persistence.IJpaDaoPersistence;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

/**
 * Abstract class that implements main CRUD JPA methods
 *
 * @author Tomislav avka
 *
 * @param <T> the type of object this interface provides
 * @param <Id> the type of Id this interface provides
 */
@Repository
@Transactional
public abstract class ADaoPersistenceImpl<T, Id extends Serializable> implements IJpaDaoPersistence<T, Id> {

    @PersistenceContext
    protected EntityManager entityManager;

    @Value("${spring.jdbc.batch_size}")
    private Integer batchSize;

    public EntityManager getEntityManager() {
        return entityManager;
    }

    public void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    protected abstract Class<T> getType();

    public T findOne(Integer id) {
        return entityManager.find(getType(), id);
    }

    @Override
    public void persist(T entity) {
        entityManager.persist(entity);
    }

    @Override
    public void update(T entity) {
        entityManager.merge(entity);
    }

    @Override
    public <T extends IIdentifier> Collection<T> bulkSave(Collection<T> entities) {
        final List<T> savedEntities = new ArrayList<>(entities.size());
        int i = 0;
        for (T t : entities) {
            savedEntities.add(save(t));
            i++;
            if (i % batchSize == 0) {
                // Flush a batch of inserts and release memory.
                entityManager.flush();
                entityManager.clear();
            }
        }
        return savedEntities;
    }

    @Override
    public <T extends IIdentifier> T save(T entity) {
        T result;
        if (entity.getId() == null) {
            getEntityManager().persist(entity);
            result = entity;
        } else {
            result = getEntityManager().merge(entity);
        }
        return result;
    }

    @Override
    public T findById(Id id) {
        return entityManager.find(getType(), id);
    }

    @Override
    public void delete(T entity) {
        T entityForDeletion = entityManager.contains(entity) ? entity : entityManager.merge(entity);
        entityManager.remove(entityForDeletion);
    }

    @Override
    public void delete(List<T> entities) {
        if (!entities.isEmpty()) {
            Query query = entityManager.createNamedQuery(getType().getSimpleName() + ".deleteItems");
            query.setParameter("forDeletion", entities);
            query.executeUpdate();
        }
    }

    @Override
    public List<T> findAll() {
        return entityManager.createNamedQuery(getType().getSimpleName() + ".findAll", getType()).getResultList();
    }

    @Override
    public void deleteAll() {
        entityManager.createNamedQuery(getType().getSimpleName() + ".deleteAll", getType()).executeUpdate();
    }
}