@Override
	public void actionPerformed(ListingActionContext context) {
		DataType dt = plugin.getCurrentDataType(context);
		dt = cycleGroup.getNextDataType(dt, true);
		if (dt != null) {
			if (!plugin.createData(dt, context, false, false)) {
				plugin.createData(DataType.DEFAULT, context, true, false);
			}
		}
	}
<code>CycleGroupAction</code> cycles data through a series
of data types defined by a <code>CycleGroup</code>.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/CycleGroupAction.java