Vfrdtyky

I'm working on my first web app with Spring-boot and hibernate.

I've written my first DAO like this :

package myapplication.orderinfo;



import java.util.List;



import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.Transaction;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Component;



import javax.persistence.EntityManagerFactory;

import javax.persistence.TypedQuery;

import javax.persistence.criteria.CriteriaBuilder;

import javax.persistence.criteria.CriteriaQuery;

import javax.persistence.criteria.Root;



@Component

public class OrderInfoDaoImpl implements OrderInfoDao {



    @Autowired

    private EntityManagerFactory entityManagerFactory;



    public List<OrderInfo> getOrderInfoDetails() {

        Session session = entityManagerFactory.unwrap(SessionFactory.class).openSession();

        CriteriaBuilder builder = session.getCriteriaBuilder();

        CriteriaQuery criteria = builder.createQuery(OrderInfo.class);

        Root contactRoot = criteria.from(OrderInfo.class);

        criteria.select(contactRoot);

        return session.createQuery(criteria).getResultList();



    }



    public List<OrderInfo> getOrderInfo(String typeName) {

        Session session = entityManagerFactory.unwrap(SessionFactory.class).openSession();

        CriteriaBuilder builder = session.getCriteriaBuilder();

        CriteriaQuery criteria = builder.createQuery(OrderInfo.class);

        Root contactRoot = criteria.from(OrderInfo.class);

        criteria.where(builder.equal(contactRoot.get("typeName"), typeName));

        return session.createQuery(criteria).getResultList();



    }

}

Is it correct to call the entityManagerFactory in each method like this?
I've read some articles on this, I understood that the session is closed by the tool at the end of each query, is this correct?

Everything looks fine at startup, but after a few queries in the application I've got this kind of crash :

Hibernate: select distinct orderinfo0_.projectLeader as col_0_0_ from t_orderInfo orderinfo0_

2018-11-12 15:12:11.746  WARN 11360 --- [nio-8080-exec-7] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 0, SQLState: null

2018-11-12 15:12:11.747 ERROR 11360 --- [nio-8080-exec-7] o.h.engine.jdbc.spi.SqlExceptionHelper   : HikariPool-1 - Connection is not available, request timed out after 30000ms.

2018-11-12 15:12:11.752 ERROR 11360 --- [nio-8080-exec-7] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path  threw exception [Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection] with root cause



java.sql.SQLTransientConnectionException: HikariPool-1 - Connection is not available, request timed out after 30000ms.

        at com.zaxxer.hikari.pool.HikariPool.createTimeoutException(HikariPool.java:669) ~[HikariCP-2.7.9.jar:na]

I'm wondering if this coming from my implementation / usage of the Hibernate session.

Any help will be appreciate :o)
Thanks

The reason is that you don't close a session. Also, better, to properly work with transactions.

You can check this approach, if you want to work with the session and tranaxctions manually
https://stackoverflow.com/a/36278975/3405171

Probably you will need to read about Spring @Transactional annotation and Spring Data, if you have not done it yet.