The `getString()` method will never throws an exception, take a look 
on [SafeResourceBundle](https://github.com/caelum/vraptor4/blob/master/vraptor-core/src/main/java/br/com/caelum/vraptor/util/SafeResourceBundle.java)'s `handleGetObject` method:
```java
@Override
protected Object handleGetObject(String key) {
	try {
		return delegate.getString(key);
	} catch (MissingResourceException e) {
		return "???" + key + "???";
	}
}
```