me.alidg.errors.annotation

Annotation Type ExposeAsArg

@Documented
 @Retention(value=RUNTIME)
 @Target(value={FIELD,METHOD})
public @interface ExposeAsArg

Annotate fields/methods inside an exception with this annotation to expose its value or return value for message interpolation. This way we can convey some information from the exception to the translated message. For example, suppose we defined an exception like the following:

     @ExceptionMapping(statusCode=BAD_REQUEST, errorCode="user.exists")
     public class UserExistsException extends RuntimeException {
         @ExposeAsArg(0) private final String username;

         // constructor and etc.
     }
 

With this setting, when the exception happens, the AnnotatedWebErrorHandler would pick the error code from the annotation and find an appropriate message for the error code. By annotating the username property with the ExposeAsArg annotation, we can use the username value to report it in the translated error message:

     user.exists=Another user with {0} username is already exists.
 

When interpolating the error message from the error code, the {0} would be replaced with the username value exposed with:

     @ExposeAsArg(0) private final String username;
 

Author:

Ali Dehghani

See Also:

ExceptionMapping, AnnotatedWebErrorHandler

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
int	value Determines the index of the to-be-exposed argument.

Element Detail

value

public abstract int value

Determines the index of the to-be-exposed argument.

Returns:

The argument index.