Turn off Validation in Eclipse Designer

So I have a method on JavaDelegate called setParameter that does the following to set a list of expressions

public void setParameter (Expression expression) {
	if(parameters == null)
		parameters = new ArrayList<Expression>();

This is so I can add a list of parameters:


When I try to add another field with the same name I get the following:


In order to get this to work, I have to open the XML and change the values so I can have duplicates and everything work as it is supposed to.

Is there another way I should be doing this to get the same functionality?

The code for the Eclipse designer hasn’t been worked on for a long time. Any reason why you’re using it?