After developing mappings in XI for a month, I just don't see any good reasons to use Graphical mappings over Java mappings. Maybe some experienced users here can give me some valid reasons why we should choose Graphical mappings. Here is what I think:
Disadvantages of Graphical mappings:
1. No way to perform automated unit testings. This is probably the biggest reason I hate it. You can do some tests manually when you work in Integration Builder. But there is no way you can write some unit testing utilities to automate the task.
2. Complexity. Even for some simple requirements, your Graphical mappings can become complicated and hard to understand. A lot of times, I find myself staring at several dozens of graphical nodes and try to understand what it does.
3. Impossible to reuse. This is totally against the DRY (Don't repeat yourself) principle. For example, to generate messages for JDBC adapter, it is common to have two identical fields for primary keys: one in the access node and another in the key node. If you change the mapping logic in one, you have to remember to change the other.
Advantage with Java mappings:
1. Fully automated unit testing. You can create JUnit tests along with your Java mapping classes and use Maven or other build tools to perform automated unit testing.
2. Your choice of XML parsing and binding. With Java mapping, you can choose any open source framework for XML parsing and binding. For example, with XMLBeans, I can convert XML input message to a Java object, transform to another Java object and write to output message. And each Java object is generated from its corresponding XML schema.
3. Highly reusable. We can use fundamental object-oriented designs to create highly reusable mapping components.
4. Better version control. Since the mappings are just Java classes, we can use CVS or SVN to track code changes.
5. Better build tools. We can fully utilize build tools like Ant and Maven to automate the build, unit tests, or even generate documents and mapping web sites.
So do you guys agree? Maybe I am still new to XI or I am missing some important things. But at this point, I just don't see why I should use Graphical mappings. Is there anyone developing XI interfaces completely with Java mappings?
Thanks in advance for any comments!