I'm new to JPA. I am following this guide: https://www.baeldung.com/spring-boot-hibernate
I am using H2 database and Intellij Idea. According to the guide #Entity annotation would create book table.
Entity class:
Database connection:
Logs:
application.properties:
spring.jpa.hibernate.ddl-auto=create
I had the same problem.
Soln: make sure your entity / Model class class is within you com.package package. otherwise it will run the classes and never map the entities.enter image description here
for my case I had to make sure it under the com package and not java package
Related
I'm having a JPA-Project in IntelliJ Idea and there are some entities my colleague mapped some time ago. Now the DB team added a bunch of tables I'm trying to add as entities to the Java-Project. But when I'm trying to map a new entity to a existing entity IntelliJ Idea doesn't know the entity. So I'm wondering, if the only way is to re-import the table?
BankEntity exists in the JavaProject, but the mapper doesn't recognize it.
Thanks !
If it is an entity that is newly added to the Intellij project, it is unaware of the related table in the database.
You have to Generate Persistence Mapping -> By Database Schema and choose/define the the datasource and then import the table. If the definition of an already mapped entity have been changed(e.g. new column added), then a refresh might help.
I'm going to answer my own question: When generating the entities, Intelli recognizes that there is an existing entity and only add the new attributes to that class. It's somehow confusing, that you have to select the entity like a new entity...but it work's.
I want to use a simple class with hibernate annotations in a non db project.
I dont wanna dublicate the code and remove annotations.
Is there a way for doing this like using annotations in subclass for parent class's attributes. So i can share the parent class.
Any help would be great, thanks.
Edit:
For example: I have a class:
#Entity
#Table(name = "Sample")
Class Sample{
#Column(name = "attr1")
private String attr1;
// getter setters etc.
}
This class works good for a java project with db dependencies set.
But I serve a restful service with this class.
My client app do not need any db related functions so I dont include any db related jars.
So this is my problem I want to use same classes since both are common for two projects. But I do not need db jars which leads to #Entity annotations to compile errors.
If there is some way to do this, I would be very happy.
Thanks alot.
use hibernate validation groups
Basic Validation Example
create 2 validation groups and use one of them for db project and other for not db project
I am using Hibernate as ORM for my project. I use mysql Database
I have a table "Products" inside DB "catalog".
I have put the #Table(name="Products",schema="catalog") annotation for the entity Products in my application.
However when I try to run the application I get the below exception. Can you please help me resolve this issue?
Exception:
Exception in thread "main" org.hibernate.HibernateException: Missing table:Products
at org.hibernate.cfg.Configuration.validateSchema(Configuration.java:1281)
at org.hibernate.tool.hbm2ddl.SchemaValidator.validate(SchemaValidator.java:155)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:508)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1769)
at org.eros.purchase.db.utils.HibernateUtil.configure(HibernateUtil.java:17)
at Test.main(Test.java:14)
Any thoughts on how I can fix this?
Please update your hibernate.cfg.xml file by adding this property
<property name="hibernate.hbm2ddl.auto">create</property>
or
<property name="hibernate.hbm2ddl.auto">update</property>
I got the same exception from hibernate. In my case, it was because the database user was not properly authorized to see the tables. The tables were definitively there on the database.
After I assigned the roles db_datareader to the user for this database it worked.
However, in another case, where the tables weren't actually there, I got exactly the same exception from hibernate. I cases where the tables are there, I think hibernate might show no more information because of security reasons.
I think your mapping is referring to User table which is actually not in database. .
so check your xml mapping of hibernate
package com.mypackage;
import javax.persistence.Entity;//first check two annotations belong to right package
import javax.persistence.Table;
#Entity
#Table(name = "Products",schema="catalog")
public class Products{
//entity attributes
}
//second check mapping file (if use)i.e register Products class with right spelling
// or third check Hibernate util if we are register mapping class like this
public class CustomHibernateUtil{
private static Configuration getConfiguration(){
configuration.addAnnotatedClass(Products.class);
return configuration;
}
}
I have an issue testing a Hibernate application which queries multiple catalogs/schemas.
The production database is Sybase and in addition to entities mapped to the default catalog/schema there are two entities mapped as below. There are therefore three catalogs in total.
#Table(catalog = "corp_ref_db", schema = "dbo", name = "WORKFORCE_V2")
public class EmployeeRecord implements Serializable {
}
#Table(catalog = "reference", schema = "dbo", name="cntry")
public class Country implements Serializable {
}
This all works in the application without any issues. However when unit testing my usual strategy is to use HSQL with hibernate's ddl flag set to auto and have dbunit populate the tables.
This all works fine when the tables are all in the same schema.
However, since adding these additional tables, testing is broken as the DDL will not run as HSQL only supports one catalog.
create table corp_ref_db.dbo.WORKFORCE_V2
user lacks privilege or object not found: CORP_REF_DB
If there were only two catalogs then I think it would maybe be possible to get round this by changing the default catalog and schema in the HSQL database to that one explicitly defined:
Is there any other in-memory database for which this might work or is there any strategy for getting the tests to run in HSQL.
I had thought of providing an orm.xml file which specified the default catalog and schema (overiding any annotations and having all the defined tables created in the default catalog/schema) however these overrides do not seem to be observed when the DDL is executed i.e. I get the same error as above.
Essentially, then I would like to run my existing tests and either somehow have the tables created as they are defined in the mappings or somehow override the catalog/schema definitions at the entity level.
I cannot think of any way to achieve either outcome. Any ideas?
I believe H2 supports catalogs. I haven't used them in it myself, but there's a CATALOGS table in the Information Schema.
I managed to achieve something like this in H2 via IGNORE_CATALOGS property and version 1.4.200
However, the url example from their docs did not seem to work for me, so I added a statement in my schema.xml:
SET IGNORE_CATALOGS = true;
When I annotate a class with #Entity and try to resolve the dependencies, I get to choose the package between two different packages, javax.persistence.Entity and org.hibernate.annotations.Entity
The javax package is JPA's entity-annotation, but why is there a hibernate entity-annotation and difference does it have with JPA's annotation? Is it just an extension to allow more attributes to be defined?
org.hibernate.annotations.Entity has some extra attributes that javax.persistence.Entity has not standarized. The extra features will only work if using hibernate's AnnotationConfiguration directly or if hibernate is the JPA provider.
from the FAQ:
edit: new link the specific question:
edit: new link the answer:
I use #org.hibernate.annotations.Entity and get an Unknown entity exception
Always import #javax.persistence.Entity
#org.hibernate.annotations.Entity completes #javax.persistence.Entity but is not a replacement
For instance, there is an attribute called optimisticLock, which tells hibernate whether to use the standard version column or to compare all columns when updating. This behavior is not in the JPA spec, so in order to configure it, you must use hibernate specific extension found in their own annotation.
Like this:
#Entity
#org.hibernate.annotations.Entity(optimisticLock=OptimisticLockType.ALL)
public class MyEntity implements Serializable {
...
}
#org.hibernate.annotations used in your project, if suppose you want to use JDBC template or ibatis we need to change the code. if we use javax.persistence there is no need to change the code. This is the main difference between org.hibernate.annotations and javax persistence
I'm not sure about the differences but I am sure that if you have the Hibernate jars in your classpath you are using Hibernate JPA. Hibernate provides an implementation of JPA. Even though you are using the javax.persistence package you are using Hibernate JPA.
The difference could be only in the naming. They might provide the same classes both in the Hibernate package space and the javax package space.