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
associate(Object.class, Integer.TYPE,
					new ObjectToPrimitiveValidator(Integer.TYPE));
			associate(Object.class, Byte.TYPE, new ObjectToPrimitiveValidator(
					Byte.TYPE));
			associate(Object.class, Short.TYPE, new ObjectToPrimitiveValidator(
					Short.TYPE));
			associate(Object.class, Long.TYPE, new ObjectToPrimitiveValidator(
					Long.TYPE));
			associate(Object.class, Float.TYPE, new ObjectToPrimitiveValidator(
					Float.TYPE));
			associate(Object.class, Double.TYPE,
					new ObjectToPrimitiveValidator(Double.TYPE));
			associate(Object.class, Boolean.TYPE,
					new ObjectToPrimitiveValidator(Boolean.TYPE));
		}
		/**
		 * Associate a particular validator that can validate the conversion
		 * (fromClass, toClass)
		 * 
		 * @param fromClass
		 *            The Class to convert from
		 * @param toClass
		 *            The Class to convert to
		 * @param validator
		 *            The IValidator
		 */
		private void associate(Object fromClass, Object toClass,
				IValidator validator) {
			validators.put(new Pair(fromClass, toClass), validator);
		}