I18nFormatFor

```
@Documented
@Retention(RUNTIME)
@Target({TYPE_USE,TYPE_PARAMETER})
@SubtypeOf(I18nUnknownFormat.class)
public @interface I18nFormatFor
```
This annotation indicates that when a string of the annotated type is passed as the first argument to MessageFormat.format(String, Object...), then the expression that is an argument to the annotation can be passed as the remaining arguments, in varargs style.
The annotation is used to annotate a method to ensure that an argument is of a particular type indicated by a format string.
Example:
```
 static void method(@I18nFormatFor("#2") String format, Object... arg2) {...}

 method("{0, number}", 2);
```
This ensures that the second parameter ("#2") can be passed as the remaining arguments of MessageFormat.format(String, Object...), when the first argument is "format".

- Required Element Summary
  
  Required Elements
  Modifier and Type Required Element Description
  
  java.lang.String value
  Indicates which formal parameter is the arguments to the format method.

- Element Detail
  - value
```
java.lang.String value
```
    Indicates which formal parameter is the arguments to the format method. The value should be # followed by the 1-based index of the formal parameter that is the arguments to the format method, e.g., "#2".
    
    Returns:
    
    # followed by the 1-based index of the formal parameter that is the arguments to the format method