Generate the database schema with Hibernate3 Maven Plugin

There is a nice Maven plugin for JPA/Hibernate that makes it possible to quickly generate the database schema (SQL) and save it in a file.
The artifactId of this plugin is hibernate3-maven-plugin.
It will scan all JPA annotations in the class files of the entities and generate the corresponding SQL queries.
A persistence.xml file is required.

1. With version 2.2 :

Content of the pom.xml :

<build>
  <plugins>
...
<plugin>
				<groupId>org.codehaus.mojo</groupId>
				<artifactId>hibernate3-maven-plugin</artifactId>	
                                <version>2.2</version>			
				<configuration>
		       	   <components>
						<component>
							<name>hbm2ddl</name>
							<implementation>jpaconfiguration</implementation>																									
						</component>							
					</components>
				   <componentProperties>
                    <drop>true</drop>
                    <create>true</create>
                    <export>false</export>
                    <format>true</format>                    <outputfilename>schema-${DataBaseUser}-${DatabaseName}.sql</outputfilename>
                    <persistenceunit>myPU</persistenceunit>
                    <propertyfile>src/main/resources/database.properties</propertyfile>
                </componentProperties>
			  </configuration>		
			  <dependencies>
			  	<dependency>
					<groupId>com.oracle</groupId>
					<artifactId>ojdbc14</artifactId>
					<version>10.2.0.2.0</version>
				</dependency>			  
			  </dependencies>					
		</plugin>
	  </plugins>
	</build>


It is important to set the export property to false, so that the plugin does not drop and recreate the database.
Here is the content of the database.properties file:

hibernate.connection.driver_class=oracle.jdbc.driver.OracleDriver
hibernate.connection.url=jdbc:oracle:thin:@123.45.678.9:1521:myDataBase
hibernate.connection.username=user1
hibernate.connection.password=pwd1
hibernate.dialect=org.hibernate.dialect.Oracle10gDialect

Use the following goal :

compile hibernate3:hbm2ddl

The file will be created in the target folder. More exactly in /target/hibernate3/sql


2. With version 3.0-SNAPSHOT


There is a more recent version of the plugin (3.0-SNAPSHOT) but it is a SNAPSHOT version, so it is not recommended to use it in projects for various reasons (for instance it would be a problem to generate releases).
Anyways, here is the configuration that worked for me, for this version of the plugin :

<plugin>
				<groupId>org.codehaus.mojo</groupId>
				<artifactId>hibernate3-maven-plugin</artifactId>			
        <version>3.0-SNAPSHOT</version>		
				<configuration>
		       	   <components>
						<component>
							<name>hbm2ddl</name>
							<implementation>jpaconfiguration</implementation>																									
						</component>							
					</components>
				   <hibernatetool>				      
				      <classpath>
				         <path location="${project.build.directory}/classes" />
				         <path location="${project.basedir}/src/main/resources/META-INF/" />				         				         
				      </classpath>				       
				      <jpaconfiguration persistenceunit="myPU" 
				         propertyfile="src/main/resources/database.properties"  />				      
				      				      
				      <hbm2ddl create="true" export="false" drop="true" outputfilename="schema1.sql"
				         format="true" console="true"/>
				   </hibernatetool>
			  </configuration>		
		</plugin>

This version does not need the presence of the database driver as a direct dependency of the plugin.
The file will be created in the target folder. More exactly in /target/sql/hibernate3 (not the same folder hierarchy as with the version 2.2 of the plugin).
Links :
http://mojo.codehaus.org/maven-hibernate3/hibernate3-maven-plugin/hbm2ddl-mojo.html