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.).
tests/org.eclipse.jface.tests.databinding/src/org/eclipse/core/tests/databinding/UpdateValueStrategyTest.java
public void testCachesDefaultedValidators() throws Exception {
		WritableValue source = WritableValue.withValueType(String.class);
		WritableValue destination = WritableValue.withValueType(Integer.class);
		
		UpdateValueStrategyStub strategy = new UpdateValueStrategyStub();
		strategy.fillDefaults(source, destination);
		
		IValidator validator = strategy.validator;
		assertNotNull(validator);
		
		strategy = new UpdateValueStrategyStub();
		strategy.fillDefaults(source, destination);
		
		assertSame(validator,strategy.validator);
	}
	
	private void assertDefaultValidator(Class fromType, Class toType, Class validatorType) {
		WritableValue source = WritableValue.withValueType(fromType);
		WritableValue destination = WritableValue.withValueType(toType);
		
		UpdateValueStrategyStub strategy = new UpdateValueStrategyStub();
		strategy.fillDefaults(source, destination);
		
		IValidator validator = strategy.validator;
		assertNotNull("validator not null", validator);
		assertTrue("converter instanceof " + validatorType, validatorType.isInstance(validator));
	}
	
	class UpdateValueStrategyStub extends UpdateValueStrategy {