How to create JPA project with Maven and MySQL

Source code: https://github.com/suddeb/PlayWithHibernate/tree/master/BasicJpaTest

Java Persistency API 2.0 (JPA): Hibernate JPA Metamodel Generator With Eclipse and Maven

One of the key features introduced in JPA 2.0 is the Criteria API, which brings a unique capability to the Java language: a way to develop queries that a Java compiler can verify for correctness at compile time. The Criteria API also includes mechanisms for building queries dynamically at run time.

In this post, I will share my experience how I configured my Eclipse to create Static Meta Model classes.

Since the Static Meta Model files are generated classes and should automatically changed for each @Entity modification they should placed in the target folder and not comitted to the repository.

Below are the steps that you have to follow:

1. Update pom.xml file:
Please update your pom.xml file with the below code under <dependencies></dependencies>

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-jpamodelgen</artifactId>
    <version>1.3.0.Final</version>
</dependency>

<dependency>
    <groupId>org.hibernate.javax.persistence</groupId>
    <artifactId>hibernate-jpa-2.0-api</artifactId>
    <version>1.0.1.Final</version>
</dependency>

2. Configure Eclipse:
Right click on your project -> properties -> Java compiler-> Annotation processing -> mark "enable project specific settings" (rather all the checkboxes on that screen), in the Generated Source Directory put "target/metamodel". 
Screenshot given below:

Once done, Inside the Annotation processing item there is a Factory Path item. You have to enable this where you have to set the jar you imported via maven to generate the classes. 
You can do it by clicking Add Variable -> M2_REPO -> Extend -> and choose the following path : 

org\hibernate\hibernate-jpamodelgen\1.3.0.Final\hibernate-jpamodelgen-1.3.0.Final

Below is the screenshot:

You have to make sure only that path is checked.

3. Final steps/Adjust Classpath:
Please make sure the target/metamodel folder is on your classpath (right click-> build path -> ad as source folder).

That's all. From now on every change in Entity Classes will trigger automatic Static Meta Model Generation.

Finally your project structure should look like:

Integrate Maven with Eclipse

While developing applications with Eclipse, if you have to move from Eclipse to Command Prompt, then after sometime you will feel irritated. That is why it is good to integrate Maven with Eclipse.

Here I will share my experience how I Integrated Maven with Eclipse. Hope it will help you guys:

Tools Needed:

1. Eclipse.
2. Maven

1. Installing Eclipse:
You can go to Eclipse's website and download the latest version of Eclipse to your machine. Once downloaded, extract the downloaded Zip file. That's all. Start enjoying Eclipse now. :-)

2. Integrate Maven with Eclipse:

• Select Help > Install New Software. This should display the "Install" dialog.
• Paste the Update Site URL (http://download.eclipse.org/technology/m2e/releases) into the field named "Work with:" and press Enter. Pressing Enter should cause Eclipse to update list of available plugins and components.
• Choose the component, Click Next. Eclipse will then check to see if there are any issues which would prevent a successful installation.
• Click Next and agree to the terms.
• Click Finish to begin the installation process. Eclipse will then download and install the necessary components.
• Once the installation process is finished, Eclipse will ask you if you want to restart the IDE.

Done. You configured Maven correctly. Enjoy coding ;-)