Bug 183890 [DataBinding] Default converter for numbers to numbers
We don't currently default converters for converting between numbers (e.g. int to double, long to int, etc.).
bundles/org.eclipse.core.databinding/src/org/eclipse/core/databinding/UpdateValueStrategy.java
/**
		 * Return an IValidator for a specific fromClass and toClass.
		 * 
		 * @param fromClass
		 *            The Class to convert from
		 * @param toClass
		 *            The Class to convert to
		 * @return An appropriate IValidator
		 */
		private IValidator get(Object fromClass, Object toClass) {
			IValidator result = (IValidator) validators.get(new Pair(fromClass,
					toClass));
			if (result != null)
				return result;
			if (fromClass != null && toClass != null && fromClass == toClass) {
				return new IValidator() {
					public IStatus validate(Object value) {
						return Status.OK_STATUS;
					}
				};
			}
			return new IValidator() {
				public IStatus validate(Object value) {
					return Status.OK_STATUS;
				}
			};
		}
	}
}