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If it contains "XML Editor", you are done and may click OK.  Otherwise, you'll need to add it:

Click 'Add'.  Select "XML Editor".  Click OK.

Click 'Add'.  Select "Text Editor".  Click OK.

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• Edit core/tests/AH.dfdl.xsd in eclipse. Notice that it uses xmlns="http://www.w3.org/2001/XMLSchema", which is the usual name space for XML Schema. 
• Note that the file extension ".dfdl.xsd" is the standard way to identify a DFDL schema file.
• Change one of the dfdl:inputValueCalc properties and misspell the property name. Save the file and you will NOT see any validation error.
• Change one of the attributes of the dfdl:defineVariable element, such as remove the name attribute and put in a ref="foo" attribute. Save, and you should see a validation error.
• Validation using the standard XML Schema URL will NOT validate short form DFDL annotations, nor will it care if you put a long form annotation element named dfdl:foobar. But if you do get the name of a DFDL annotation element correct, then it will validate the properties on that annotation element.

Setup Unix-Style Line Endings

Open Eclipse.

1. Go to Window -> Preferences -> General -> Workspace
2. In the bottom right of the window you'll see 'New text file line delimiter'.
3. Select 'Other'.
4. In the drop-down, select 'Unix'.
5. Click Apply.
6. Click OK.

Setup Linked Resources

Open Eclipse.

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