/** File name: AbstractDbComponentFactory.java **/


package abstractfactorypattern;

public abstract class AbstractDbComponentFactory {

    public static AbstractDbComponentFactory createDbComponentFactory(String factoryname)    {
        
        if (factoryname == "ORACLE")  {
            return new OracleDbComponentFactory();
        }
        else if (factoryname == "MYSQL")  {
            return new MysqlDbComponentFactory();
        }
        return null ;
    }
    
     public abstract AbstractDbComponent createDbComponent();

}




/** File name: AbstractDbComponent.java **/

package abstractfactorypattern;

public abstract class AbstractDbComponent {
    public abstract void execute();


}





/** File name: MysqlDbComponentFactory.java **/

package abstractfactorypattern;

public class MysqlDbComponentFactory extends AbstractDbComponentFactory {
    
    public AbstractDbComponent createDbComponent() {
        return new MysqlDbComponent() ;
    }
    
}






/** File name: OracleDbComponentFactory.java **/

package abstractfactorypattern;

public class OracleDbComponentFactory extends AbstractDbComponentFactory {
    
    public AbstractDbComponent createDbComponent() {
        return new OracleDbComponent() ;
    }
}






/** File name: MysqlDbComponent.java **/

package abstractfactorypattern;

public class MysqlDbComponent extends AbstractDbComponent {
    public MysqlDbComponent() {
        System.out.println("Creating MYSQL DB Component");
    }
    
    public void execute() {
        System.out.println("MYSQL:  Executing using MysqlDbComponent") ;
    }
}





/** File name: OracleDbComponent.java **/

package abstractfactorypattern;

public class OracleDbComponent extends AbstractDbComponent {

    public OracleDbComponent() {
        System.out.println("Creating ORACLE DB Component");
    }
    
    public void execute() {
        System.out.println("ORACLE:   Executing using OracleDbComponent") ;
    }
}





/** File name: Main.java **/

package abstractfactorypattern;

public class Main {

    public Main() {
    }

    public static void main(String[] args) {
        
        System.out.println("TEST for oracle component");
        AbstractDbComponentFactory dbcomponentfactory = 
                AbstractDbComponentFactory.createDbComponentFactory("ORACLE");
        AbstractDbComponent dbcomponent = dbcomponentfactory.createDbComponent();
        dbcomponent.execute();
        
        
        System.out.println("\n\n\nTEST for Mysql component");
        dbcomponentfactory = 
                  AbstractDbComponentFactory.createDbComponentFactory("MYSQL");
        dbcomponent = dbcomponentfactory.createDbComponent();
        dbcomponent.execute();
    }
}





Following output is generated:


TEST for oracle component
Creating ORACLE DB Component
ORACLE:   Executing using OracleDbComponent



TEST for Mysql component
Creating MYSQL DB Component
MYSQL:  Executing using MysqlDbComponent