$.DefaultDAO.java Source code

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Here is the source code for $.DefaultDAO.java

Source

    #set($symbol_pound='#')#set($symbol_dollar='$')#set($symbol_escape='\')
/**
 * This software is licensed under the terms of the MIT license.
 * Copyright (C) 2016 Dmytro Romenskyi
 */
package ${package}.${artifactId}.data;

    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Repository;
    import org.springframework.beans.factory.annotation.Value;
import ${package}.${artifactId}.domain.IdentifiedEntityInterface;

    import java.util.Collections;
    import java.util.List;

    /**
     * Generic class for accessing application datastorage
     */
    @Repository
    public class DefaultDAO {

        private @Value("${symbol_dollar}{app.softDeleteEnabled}") boolean softDelete;

        @Autowired
        private SessionFactory sessionFactory;

        protected Session getSession() {
            return sessionFactory.getCurrentSession();
        }

        /**
         * Checks whether the entity with provided key exists
         *
         * @param clazz entity class
         * @param id key to check
          * @return true is entity of the provided class with provided key exists; false otherwise
          */
        private <ENTITY extends IdentifiedEntityInterface> boolean exists(Class<ENTITY> clazz, Long id) {

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

            Session session = getSession();

            return session.get(clazz, id) != null;
        }

        /**
         * Gets all entities of the provided class
         * @param clazz entity class
         *
          * @return a list of all entities of provided class or empty list if there no such entities
          */
        public <ENTITY extends IdentifiedEntityInterface> List<ENTITY> getAll(Class<ENTITY> clazz) {
            Session session = getSession();

            @SuppressWarnings("unchecked")
            List<ENTITY> entities = session.createCriteria(clazz).list();

            if (entities == null) {
                entities = Collections.emptyList();
            }

            return entities;
        }

        /**
         * Creates a new entry in the datastorage with data from provided entity
         *
         * @param entity entity information to save
         *
          * @return ID of the newly created entity
          */
        public <ENTITY extends IdentifiedEntityInterface> Long create(ENTITY entity) {
            if (entity == null) {
                throw new IllegalArgumentException("Invalid entity provided:[NULL]");
            }

            if (entity.getId() != null) {
                entity.setId(null);
            }

            Session session = getSession();

            return (Long) session.save(entity);
        }

        public <ENTITY extends IdentifiedEntityInterface> boolean delete(Class<ENTITY> clazz, Long id) {
            if (softDelete) {
                throw new UnsupportedOperationException("Physical delete operation forbidden");
            }

            if (id == null) {
                throw new IllegalArgumentException("Invalid value for entity ID provided:[NULL]");
            }

            if (!exists(clazz, id)) {
                // TODO add logging
                return false;
            }

            Session session = getSession();
            session.delete(session.load(clazz, id));
            return true;
        }
    }