JEE EJB - Mybatis example

Client

package example.jee6mybatis;

import javax.ejb.EJB;
import javax.ejb.Stateless;

@Stateless
public class Client {

    @EJB SessionWrapper mybatis;
    
    public void myBusinessMethod() {
    
        String result = mybatis.selectOne("my.supersecret.mapped.statemet");
        
    }
    
}

SessionFactoryWrapper

package example.jee6mybatis;

import java.sql.Connection;
import javax.annotation.PostConstruct;
import javax.ejb.Singleton;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

@Singleton
public class SessionFactoryWrapper {
    
    private SqlSessionFactory factory;
    
    @PostConstruct
    public void init() {
        factory = <builder code>;
    }

    public SqlSession getSession(Connection con) {
        return factory.openSession(con);
    }
    
}

SessionWrapper

package example.jee6mybatis;

import java.sql.SQLException;
import javax.annotation.Resource;
import javax.ejb.EJB;
import javax.ejb.EJBException;
import javax.ejb.Stateless;
import javax.sql.DataSource;
import org.apache.ibatis.session.SqlSession;

@Stateless
public class SessionWrapper {
 
    @EJB 
    SessionFactoryWrapper factory;
    
    @Resource (mappedName="java:/MyDataSource")
    DataSource ds;

    // Example interceptable wrapped method
    public <T> T selectOne(String statement) {
        try {
            SqlSession s = factory.getSession(ds.getConnection());
            T result = s.selectOne(statement);
            s.close();
            return result;
        } catch (SQLException ex) {
            throw new EJBException(ex);
        }
    }
        
}

How to use the Transaction manger if the EJB container is running on another JVM

In my Ejb I m calling many other ejb methods so how to rollback automatically if one fails.