Generate DDL with Hibernate Tools, JPA and Maven
It is very convenient to get the SQL you need to setup your database generated by you. The information is all there in your JPA annotated classes.
Hibernate Tools
Hibernate provides for that purpose the really great Hibernate Tools. But these tools are eclipse or ANT based. No official Maven support.
hibernate3-maven-plugin
Indeed there exists a Maven plugin at Codehaus, the hibernate3-maven-plugin. But this is (as the name states) only for hibernate 3.x and does not support hibernate 4.
Searching in the net revealed, that it could take a while until the new hibernate version would be supported (e.g. https://community.jboss.org/thread/203735).
Solution: ant-run Plugin
Luckily Maven has the possibility to execute ANT tasks. So the obvious solution is to just use the ant-run plugin and execute the hibernate-tools ANT target. Well, would be if you are an expert in Maven AND ANT classpaths :-). For me it took several hours to find the following solution:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 |
<plugin> <artifactid>maven-antrun-plugin</artifactid> <version>1.2</version> <executions> <execution> <phase>install</phase> <goals> <goal>run</goal> </goals> </execution> </executions> <configuration> <tasks> <property name="maven_test_classpath" refid="maven.test.classpath"></property> <path id="hibernate_tools_path"> <pathelement path="${maven_test_classpath}"></pathelement> </path> <property name="hibernate_tools_classpath" refid="hibernate_tools_path"></property> <echo message="hibernate_tools classpath: ${hibernate_tools_classpath}"></echo> <taskdef name="hibernatetool" classname="org.hibernate.tool.ant.HibernateToolTask" classpathref="maven.plugin.classpath"></taskdef> <mkdir dir="${project.build.directory}/generated-sources/hibernate"></mkdir> <hibernatetool destdir="${project.build.directory}/generated-sources/hibernate"> <classpath refid="hibernate_tools_path"></classpath> <jpaconfiguration persistenceunit="DDLGenerationUnit"></jpaconfiguration> <hbm2ddl export="false" format="true" outputfilename="database.ddl"></hbm2ddl> </hibernatetool> </tasks> <detail>true</detail> </configuration> <dependencies> <dependency> <groupid>org.hibernate</groupid> <artifactid>hibernate-tools</artifactid> <version>4.0.0-CR1</version> <exclusions> <exclusion> <artifactid>hibernate-commons-annotations</artifactid> <groupid>org.hibernate</groupid> </exclusion> </exclusions> </dependency> <dependency> <groupid>org.slf4j</groupid> <artifactid>slf4j-simple</artifactid> <version>${slf4j.version}</version> </dependency> <dependency> <groupid>org.slf4j</groupid> <artifactid>slf4j-api</artifactid> <version>${slf4j.version}</version> </dependency> <dependency> <groupid>mysql</groupid> <artifactid>mysql-connector-java</artifactid> <version>5.1.6</version> </dependency> </dependencies> </plugin> |
I use the test classpath because I already create (with the help of the jpa-maven-plugin) a persistence.xml with all classes included for testing purposes. Just added a more production like unit to be used:
|
1 2 3 4 5 6 7 8 9 |
<persistence -unit name="DDLGenerationUnit" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <class>${entityClassnames}</class> <properties> <property name="hibernate.ejb.naming_strategy" value="com.optible.jpa.naming.ImprovedEJB3NamingStrategy"></property> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect"></property> <property name="hibernate.archive.autodetection" value="class"></property> </properties> </persistence> |
and the pom plugin entries for generating the entity class list, inserting it into the template persitence.xml and adding this directory to the test classpath:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 |
<plugin> <groupid>com.edugility</groupid> <artifactid>jpa-maven-plugin</artifactid> <version>1.0</version> <executions> <execution> <id>Generate entityClassnames.properties</id> <phase>generate-resources</phase> <goals> <goal>list-entity-classnames</goal> </goals> </execution> </executions> </plugin> <plugin> <artifactid>maven-resources-plugin</artifactid> <version>2.5</version> <executions> <execution> <id>Copy persistence.xml filtered with generated entityClassnames.properties file</id> <phase>generate-resources</phase> <goals> <goal>copy-resources</goal> </goals> <configuration> <filters> <filter>${project.build.directory}/generated-test-sources/jpa-maven-plugin/entityClassnames.properties</filter> </filters> <outputdirectory>${project.build.directory}/generated-test-sources/persistence/META-INF</outputdirectory> <resources> <resource> <filtering>true</filtering> <directory>src/process/test/resources</directory> <includes> <include>persistence.xml</include> </includes> </resource> </resources> </configuration> </execution> </executions> </plugin> <plugin> <groupid>org.codehaus.mojo</groupid> <artifactid>build-helper-maven-plugin</artifactid> <version>1.7</version> <executions> <execution> <id>add-test-resources</id> <phase>generate-test-resources</phase> <goals> <goal>add-test-resource</goal> </goals> <configuration> <resources> <resource> <directory>target/generated-test-sources/persistence</directory> </resource> </resources> </configuration> </execution> </executions> </plugin> |