Validation.Required (core 2.44.0 API)

```
@Target(METHOD)
@Retention(RUNTIME)
@Documented
public static @interface Validation.Required
```
This criteria specifies that the value must be not null. Note that this annotation should only be applied to methods that return nullable objects.

- Optional Element Summary
  
  Optional Elements
  Modifier and Type Optional Element Description
  
  java.lang.String[] groups
  The groups that the annotated attribute is a member of.

- Element Detail
  - groups
```
java.lang.String[] groups
```
    The groups that the annotated attribute is a member of. A member can be in 0 or more groups. Members not in any groups are considered to be in a group consisting exclusively of themselves. At least one member of a group must be non-null if the options are to be valid.
    
    Default:
    
    {}