May I know can the Eclipse plugin Hibernate tool use to generate JPA entity #entity? The Java files that generated look like below and not JPA:
package com.test.only.model;
// Generated Jul 19, 2011 12:13:40 PM by Hibernate Tools 3.2.0.CR1
import java.math.BigDecimal;
import java.util.Date;
/**
* Account generated by hbm2java
*/
public class Account implements java.io.Serializable {
You just need to choose EJB3 + Java5 as configuration options when generating.
Learn more: http://docs.jboss.org/tools/4.0.0.Final/en/hibernatetools/html_single/index.html#jpa_annotations
I believe you can generate Hibernate annotation code by using the Hibernate Perspective -> Add Configuration… and follow the steps of this tutorial .
I suspect the JPA annotated entity can be generated if you select JPA(jdk 1.5+) or Annotation (jdk 1.5+) in the following configuration .Please try it.
Yes, it can.
Hibernate Tools, which is now available as a part of JBoss Tools, can be used for generating JPA entities as well. In fact you need to select JPA option in Hibernate Configuration which is being used for your project.
Even better would be to start off your reverse code generation as a JPA Project. Then once the project is created switch over to the Hibernate Perspective to confirm the JPA annotations option is selected in the Hibernate Configuration settings.
Following tutorial has pictorial representation of various steps involved in creating a JPA Project in Eclipse. It then shows in the Appendix section how to edit the Hibernate Configuration as well.
http://www.javabrahman.com/j2ee/how-to-setup-a-jpa-project-with-a-data-connection-for-mysql-in-eclipse/
For me changing from hibernate version 5.4 to 5.2 worked while configuring.
and do check use Java5 syntax and Generate EJB3 annotations while code generation.
Related
I'd like to automatically generate Hibernate mappings for some Java classes I have. Basically, I'd like all objects in the class to have the equivalent of the #OneToOne annotation, and all collections to have the equivalent of the #OneToMany annotation by default. I'd like to be able to fine-tune this later, but 99% of my data works this way, and it would take a very long time to go through all the classes and add the annotations manually.
Is this possible?
edit: Sorry, I think omitted something very important: I'd actually like to generate these default annotations from classes, not from a database. I would still have to design about 40 tables if I were to start with the database, but I already have a package containing all those classes. Is it possible to generate the proper mappings based on existing Java classes?
Yes, in eclipse there is a plugin called hibernate tools from jboss, which can generate mapping from a existing database.
You can generate all hibernate files both xml and annotations variant.
Just Google Hibernate Tools to know how to use it.
Thanks !!
If you are creating new classes then you can create the database structure first and then create classes using database. In eclipse, hibernate provides Hibernate code generation feature. You can use that.
Hibernate Tools has 2 diffeent configurations regarding this topic.
You got the Console config with the options Hibernate 3.5/3.6/4.0 plus
and Core / (Hibernate) Annotations / JPA Annotations
and later in launch code generator menu we already can select in exporters: Java 5+ and EJB options.
But the behaviour seeems a bit inconsistent for me, as marking JPA annotations without EJB option erases any annotation. So is there any way to make Hibenrate generate non-EJB JPA annotations code (DAO+POJOS)?
THe thing is I don't want to get an injected EntityManager, and I am not using any EJB container but SDK. I am wondering whther there is an smart code generation in that case
I have a strange issue my ear project:
I have put the correct annotations on my entity class:
#Entity
#Table(name = "PRODUCTS")
But when I deploy my application on glassfish 3.1.2.2, I find that JPA has created the tables with lowercase chars
I am using EclipseLink 2.4.1
Please Help me.
I got the solution from Brian Vosburgh's comment:
In the windows version of MySQL the names of table are set to lower case. On linux, by default, this configuration is disabled, and the tables'names set by JPA are applied to MySQL without modification.
To make it working on windows as like linux, add the line:
lower_case_table_names=0
Thank you for your help, specially Brian Vosburgh
I found a property the makes all the difference.
In the EclipseLink wizard (generate entities from tables), third page (Customize Defaults), I checked the "Always generate optional JPA annotations and DDL parameters" option.
This option writes the below annotation in the Entity class:
#Table(name="TableName")
The correct table name letter case will be used.
I'm using hibernate tools under Eclipse Indigo. The Hibernate Console has Annotations option selected and hibernate version is 4.0.
The hibernate tools wizard generates annotations only when I choose Generate EJB3 Annotations option. This introduces a dependency on EJB, and I don't want it.
How do I convince Hibernate tools to generate POJOs (via reverse engineering) that uses plain (non jpa) hibernate annotations?
Then you probably want to specify "Hibernate 3.x" as version, not 4.0. If I remember correctly, Hibernate 4.0 provides JPA-only annotations, plus some few extra ones that would be "extensions".
Now, I think the real question is: why do you want to get rid of JPA? Note that EJB3 != JPA. In fact, JPA is a replacement for what was once known as EJB Entity Beans. And that adding JPA dependency will not add an EJB dependency in your project.
I got an existing table in Oracle database how can I generate my Hibernate Java class etc from this table?
Using Eclipse 3.2, Java 5
Do you mean generate a POJO that maps to the table? You can use the Hibernate Tools plugin for Eclipse. Otherwise you can create the POJO manually and map it to the table using Hibernate Annotations.
The Hibernate Tools for Eclipse and Ant does support reverse engineering. From the website:
Reverse Engineering: The most powerful feature of Hibernate Tools is a database reverse engineering tool that can generate domain model classes and Hibernate mapping files, annotated EJB3 entity beans, HTML documentation or even an entire JBoss Seam application in seconds!
Refer to the provided link for more details.