This is one of the best descriptions of how to use the Hibernate tools to reverse engineer a DB into ,hbm and .java files automatically.
I will post the description here if it will ever disappear.
- Download the hibernate-tools jar. [i]
- Extract the jar to plugins folder of Eclipse.
- Start eclipse.
- Click on [File -> New -> Other -> Hibernate -> Hibernate Configuration File] and create a cfg file. The following properties should be specified : jdbc url , username, password, DB schema, driver class and dialect.
- Click on [File -> New -> Other -> Hibernate -> Hibernate Console Configuration ] and create a new console configuration. Add the jar file that contains your DB driver in the classpath section at the bottom.
- Enter the name of the console configuration. Click Browse button against the Configuration file and select the cfg.xml file created in step 4.
- Click on [File -> New -> Other -> Hibernate -> Hibernate Reverse Engineering File(reveng.xml) ] and select the location of the file.
- Select the cfg.xml file created in step 4 as the Console Configuration. Click on include button and specift the schema and table name(s) to reverse engineer. Multiple table names can be specifed using sql wild char (eg: TBL_%). Click Finish.
- Click on the Hibernate icon in the tool bar and select the [Hibernate Code Generation ..] option.
- Right click on the [Hibernate Code Generation]tree node and select New.
- Give the name of the configuration and select the console configuartion created in setp 5 and reveng.xml created in step6-7. Also select the Output Directory,
- Go to the Exporters tab and check Generate domain code(.java) and Generate mappings (hbm.xml). Click run.
- The hibernate mapping xml files and Java classes will be created in the output directory specified in step 11.
UPDATE: [i] Some of the new versions of eclipse come with the tools pre installed, if your version has the tools preinstalled jump to step 4