Maven + Spring + Hibernate: hibernate3-maven-plugin hbm2ddl fails for reason “Caused by: java.lang.NullPointerException”

Question

I had to downgrade Hibernate from version 4 to version 3 (3.3.2.GA to be specific), due to current lack of support for Hibernate 4 within Spring, and now the project fails t

Answer 1

I faced the same problem while trying to make maven bootstrap a database from a hibernate model (issue described in Generate database schema (Hibernate) on maven test).

I got hbm2ddl working quite well with the following combination of versions: Hibernate (runtime): 4.1.7.Final hibernate3-maven-plugin: 3.6.10.Final, specified plugin version 2.2 hibernate3-maven-plugin's hibernate-validator dependency: 4.2.0.Final

Below the relevant parts of the pom:

Versions:

    4.1.7.Final
    3.6.10.Final

hibernate3-maven-plugin's definition:

    
        
            org.codehaus.mojo
            hibernate3-maven-plugin
            2.2
            
                
                    
                        hbm2ddl
                        jpaconfiguration
                    

                

                
                    schema.ddl
                    true
                    false
                    true
                    false
                    true
                    target/test-classes/application.properties
                    ${skipTests}
                
            
            
                
                    process-classes
                    
                        hbm2ddl
                    
                
            
            
                
                    org.hibernate
                    hibernate-entitymanager
                    ${hibernate.maven.plugin.version}
                    
                        
                            cglib
                            cglib
                        
                        
                            commons-logging
                            commons-logging
                        
                    
                
                
                    org.hibernate
                    hibernate-core
                    ${hibernate.maven.plugin.version}
                    
                        
                            cglib
                            cglib
                        
                        
                            commons-logging
                            commons-logging
                        
                    
                
                
                    org.hibernate
                    hibernate-validator
                    4.2.0.Final
                

            
        

    

Runtime dependencies:

    
        org.hibernate
        hibernate-core
        ${org.hibernate.version}
    

    
        org.hibernate
        hibernate-entitymanager
        ${org.hibernate.version}
    

I hope this helps.