Auto generate data schema from JPA 2.1 annotated entity classes without a database connection

Question

Two years ago I was working on a project using:

• spring 4.0.3.RELEASE
• jpa 2.0
• hibernate 4.2.7.Final
• java 1.6.X

This pr

Answer 1

I follow your idea of using h2 with Mysql dialect but using JPA Persistence.generateSchema(...).

It does work except all commands are not separated by a semi-column...

How can this been done using JPA 2.1?

Otherwise I will switch to your solution.

import java.util.Properties;

import javax.persistence.Persistence;
import javax.persistence.PersistenceException;

import org.hibernate.jpa.AvailableSettings;

/**
 * Generate DDL with hibernate 4+/5:
 * http://stackoverflow.com/questions/27314165/generate-ddl-script-at-maven-build-with-hibernate4-jpa-2-1/27314166#27314166
 * @author dmary
 * 
 */
public class Jpa21SchemaExport {

    /**
     * 
     */
    public Jpa21SchemaExport() {
        // TODO Auto-generated constructor stub
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        execute(args[0], args[1]);
        System.exit(0);

    }

    public static void execute(String persistenceUnitName, String destination) {
        System.out.println("Generating DDL create script to : " + destination);

        final Properties persistenceProperties = new Properties();

        // XXX force persistence properties : remove database target
        persistenceProperties.setProperty(org.hibernate.cfg.AvailableSettings.HBM2DDL_AUTO, "");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_DATABASE_ACTION, "none");

        // XXX force persistence properties : define create script target from metadata to destination
        // persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_CREATE_SCHEMAS, "true");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_ACTION, "create");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_CREATE_SOURCE, "metadata");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_CREATE_TARGET, destination);

        persistenceProperties.setProperty(AvailableSettings.JDBC_DRIVER,"org.h2.Driver");
        persistenceProperties.setProperty(AvailableSettings.JDBC_URL, "jdbc:h2:mem:export");
        persistenceProperties.setProperty(AvailableSettings.JDBC_USER, "sa");
        persistenceProperties.setProperty(AvailableSettings.JDBC_PASSWORD, "");

        persistenceProperties.setProperty(org.hibernate.cfg.AvailableSettings.DIALECT, "com.wiztivi.sdk.persistence.MySQL5InnoDBUTF8Dialect");

        try
        {
            Persistence.generateSchema(persistenceUnitName, persistenceProperties);
        } catch (PersistenceException pe)
        {
            System.err.println("DDL generation failed: ");
            pe.printStackTrace(System.err); 
        }
    }