Latest Questions tagged Jpa

Browse all latest questions tagged Jpa

Published 07 Sep, 2022
Java - How to filter a PostgreSQL array column with the JPA Criteria API?

I am using: Hibernate 4.3.5 Spring JPA 1.6.0 Javax Persistence API 2.1 The "refcodemailing" column is defined as an array of int: int[] My entity object: @Entity @Table public class CalendarEven...

Published 07 Sep, 2022
Java - Set environment variable values in persistence.xml from Eclipse

I'm using OpenShift, and I'm trying to deploy my application to a local Tomcat instance for faster development. I'm using EclipseLink for DB transactions, and I've provided the environment variables O...

Published 07 Sep, 2022
Java - JPA select query with where clause

I want to write a select statement but can't figure out how to write the where clause... My code: CriteriaQuery query = entityManager.getCriteriaBuilder().createQuery();

Published 07 Sep, 2022
Java - JPA , many-to-many relation, deleting all previous relations and entering the new relations

here i am trying out many-to-many relationship in JPA, I'v created tables "tblcourse" and "tblStudent", a student can register to many courses, create table tblcourse( id integer primary key,...

Published 04 Oct, 2022
Java - Hibernate - Column cannot be null

I'm doing a simple exercise to learn JPA. When I try to delete an entity of type User, which has a Collection of the other entity Score (annotated with @OneToMany) I get this error: java.sql.SQLInteg...

Published 06 Sep, 2022
Java - How to set autogenerated Id manually?

I have an entity called Task and it has taskId field. Problem is I need to create/update some specific tasks and JPA autogenerator doesn't allow me to set taskId manually.(It overrides my taskId) Is...

Published 08 Oct, 2022
Java - How to avoid join 'explosions' in JPA with Hibernate when fields from multiple tables are needed?

Let's say I have the following method in a JpaRepository: @EntityGraph(value = "Subject.allJoins", type = EntityGraphType.FETCH) @Query("select s from Subject s" + FIND_QUERY_WHERE) Page<S...

Published 05 Sep, 2022
Java - JPA CriteriaQuery compare Timestamp ignore time portion

Let say I have a column in Oracle DB like this: SOMETHING_TS TIMESTAMP WITH TIME ZONE And I would like to use CriteriaQuery to filter by this column. I can used native query to achieve this:...

Published 19 Aug, 2022
Java - What is the Java annotation in Hibernate used to auto increment a MySQL Primary Key - @Id

In this code I need the id to be the primary key and also it must be incremented. is getter and setter required for id ? @Entity public class Contact { @Id private Integer id; private String firstNa...

Published 07 Sep, 2022
Java - How to specify SQL comments through JPA annotations?

Is there any way to specify SQL comments through JPA annotations? Comments for tables and columns.

Published 11 Oct, 2022
Java - Keep getting "java.lang.IllegalArgumentException: No query defined for that name" even though I have @NamedQuery with an appropriate name

I have Hibernate JPA application. I keep getting "java.lang.IllegalArgumentException: No query defined for that name [Singer.findAll]" in the function from DAO class, even though I defined the name in...

Published 07 Sep, 2022
Java - How to map a MySQL JSON column to a Java entity property using JPA and Hibernate

I have a MySQL column declared as type JSON and I have problems to map it with JPA/Hibernate. I'm using Spring Boot on back-end. Here is small part of my code: @Entity @Table(name = "some_table_n...

Published 29 Aug, 2022
Java - What is causing a unique constraint violation when using a SEQUENCE in Hibernate?

I am using the code below to generate unique IDs for an id field. It was working fine until last week. I deleted some entities using the Hibernate interface and then it started giving a unique constra...

Published 15 Sep, 2022
Java - When and why JPA entities should implement the Serializable interface?

The question is in the title. Below I just described some of my thoughts and findings. When I had a very simple domain model (3 tables without any relations), all my entities did NOT implement the Ser...

Published 07 Sep, 2022
Java - Why is bean not found during Spring Boot?

I reconfigured my DAOs to a more convenient way (by using JpaRepository) instead of doing all that boilerplate code manually. But now everytime I start the Spring Application it gives me the following...