Question

I’ve been trying to get a simple skeleton app to run (and commit to the DB) using JPA, MySQL, Hibernate & Maven, however I’m having problems.

Listed below are my 2 trivial classes, my pom.xml, and my META-INF/persistence.xml

I can build the project without any problem (mvn clean install), however running it (mvn exec:java -Dexec.mainClass=com.foo.HelloWorld -X) causes an exception, with the following StackTrace.

Any help would be greatly appreciated!

Stacktrace:

org.apache.maven.lifecycle.LifecycleExecutionException: An exception occured while executing the Java class. null
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:719)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
        at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
        at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
        at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
        at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused by: org.apache.maven.plugin.MojoExecutionException: An exception occured while executing the Java class. null
        at org.codehaus.mojo.exec.ExecJavaMojo.execute(ExecJavaMojo.java:346)
        at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
        at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
        ... 17 more
Caused by: java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:291)
        at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NoSuchMethodError: org.hibernate.event.PreInsertEvent.getSource()Lorg/hibernate/engine/SessionImplementor;
        at org.hibernate.validator.event.ValidateEventListener.onPreInsert(ValidateEventListener.java:167)
        at org.hibernate.action.EntityIdentityInsertAction.preInsert(EntityIdentityInsertAction.java:142)
        at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:65)
        at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279)
        at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:321)
        at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:204)
        at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:130)
        at org.hibernate.event.def.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:154)
        at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:110)
        at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:61)
        at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:646)
        at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:620)
        at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:624)
        at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:212)
        at com.foo.HelloWorld.create(HelloWorld.java:32)
        at com.foo.HelloWorld.main(HelloWorld.java:11)
        ... 6 more

I have the following two classes:
The Entity to store.

package com.foo;

import java.io.Serializable;

import javax.persistence.Basic;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Message {
    @Id
    @GeneratedValue
    private int id;
    @Basic
    private String message;

    public Message() {}

    public Message(String message) {
        this.message = message;
    }

    public String toString() {
        return "Greeting id=" + id + ", message=" + message;
    }
}

The Application:

package com.foo;

public class HelloWorld {
    private javax.persistence.EntityManagerFactory emf;
    private javax.persistence.EntityManager em;
    private String PERSISTENCE_UNIT_NAME = "hello-world";

    public static void main(String[] args) {
        HelloWorld hello = new HelloWorld();
        hello.initEntityManager();
        hello.create();
        //        hello.read();
        hello.closeEntityManager();
    }

    private void initEntityManager() {
        emf = javax.persistence.Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
        em = emf.createEntityManager();
    }

    private void closeEntityManager() {
        em.close();
        emf.close();
    }

    private void create() {
        em.getTransaction().begin();
        Message hello = new Message("hello world");
        Message bye = new Message("goodbye, world");
        Message[] messages = new Message[] {hello, bye};
        for (Message m : messages) {
            em.persist(m);
        }
        em.getTransaction().commit();
    }

    //    private void read() {
    //        Message m = (Message)em.createQuery("select m from Message m").getSingleResult();
    //        System.out.println("Query returned: " + m);
    //    }
}

The following is my pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

 <modelVersion>4.0.0</modelVersion>
 <groupId>com.treocht.hibernate.tutorial</groupId>
 <artifactId>hibernate-tutorial</artifactId>
 <version>1.0.0-SNAPSHOT</version>
 <name>First Hibernate Tutorial</name>


 <dependencies>

  <dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate-core</artifactId>
   <version>3.3.2.GA</version>
   <type>jar</type>
   <scope>compile</scope>
  </dependency>
  <dependency>
   <groupId>javax.persistence</groupId>
   <artifactId>persistence-api</artifactId>
   <version>1.0</version>
   <type>jar</type>
   <scope>compile</scope>
  </dependency>

  <dependency>
   <groupId>commons-logging</groupId>
   <artifactId>commons-logging</artifactId>
   <version>1.0.4</version>
  </dependency>

  <dependency>
   <groupId>hsqldb</groupId>
   <artifactId>hsqldb</artifactId>
   <version>1.8.0.7</version>
  </dependency>

  <dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate</artifactId>
   <version>3.2.2.ga</version>
  </dependency>

  <dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate-annotations</artifactId>
   <version>3.2.1.ga</version>
  </dependency>

  <dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate-entitymanager</artifactId>
   <version>3.2.1.ga</version>
  </dependency>

  <dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate-tools</artifactId>
   <version>3.2.0.beta9a</version>
  </dependency>

  <dependency>
   <groupId>c3p0</groupId>
   <artifactId>c3p0</artifactId>
   <version>0.9.1</version>
  </dependency>
  <dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-api</artifactId>
   <version>1.6.1</version>
   <type>jar</type>
   <scope>compile</scope>
  </dependency>
  <dependency>
   <groupId>mysql</groupId>
   <artifactId>mysql-connector-java</artifactId>
   <version>5.1.13</version>
   <type>jar</type>
   <scope>compile</scope>
  </dependency>
 </dependencies>

 <build>
  <!--
   we dont want the version to be part of the generated war file name
  -->
  <finalName>${artifactId}</finalName>

  <pluginManagement>
   <plugins>
    <plugin>
     <groupId>org.apache.maven.plugins</groupId>
     <artifactId>maven-compiler-plugin</artifactId>
     <configuration>
      <source>1.6</source>
      <target>1.6</target>
     </configuration>
    </plugin>
   </plugins>
  </pluginManagement>
 </build>

</project>

And I have this META-INF/persistence.xml file:

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence persistence_1_0.xsd"
 version="1.0">

 <persistence-unit name="hello-world" transaction-type="RESOURCE_LOCAL">
  <provider>org.hibernate.ejb.HibernatePersistence</provider>
  <class>com.foo.Message</class>
  <properties>
   <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/my_db" />
   <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver" />
   <property name="hibernate.connection.password" value="password" />
   <property name="hibernate.connection.username" value="username" />
   <property name="hibernate.hbm2ddl.auto" value="update" />
  </properties>
 </persistence-unit>
</persistence>

Answer 1

You’re indeed using incompatible versions of Hibernate artifacts as this can be verified using the official Hibernate Compatibility Matrix. Don’t rely on some random tutorial found around the net for that.

But since you’re using Maven, you actually don’t need to declare all Hibernate artifacts, just leverage the transitive dependencies. So just declare a dependency in the hibernate-entitymanager (especially if you’re not sure of what you’re doing):

<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-entitymanager</artifactId>
  <version>3.4.0.GA</version><!-- for JPA 1.0 -->
</dependency>

And remove these hibernate, hibernate-core, hibernate-annotations, persistence-api, slf4j dependencies.

And if you want to change the version of the sfl4j-api artifact that you get transitively, you should do that in the dependency management section:

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>1.6.1</version>
    </dependency>
  </dependencies>
</dependencyManagement>

Actually (and I’m sorry to say so) your whole pom is a big mess, try to spend some time cleaning it. Use mvn dependency:tree (or some visual fronted offered by your IDE) to do so.

And let me insist, don’t rely on some random (and wrong) tutorial found around the net, leverage Maven transitive dependency mechanism.

PS: As of Hibernate 3.5, the various projects (Hibernate Annotation, Hibernate EntityManager) have been merged back to Hibernate Core and their versions are synchronized which simplifies a lot version management, even for Maven users.