Comment (Hibernate Javadocs)

```
@Target({METHOD,FIELD,TYPE})
@Retention(RUNTIME)
@Repeatable(Comments.class)
public @interface Comment
```
Specifies a comment that will be included in generated DDL.
By default, if on() is not specified:
- when a field or property is annotated, the comment applies to the mapped column,
- when a collection is annotated, the comment applies to the collection table, and
- when an entity class is annotated, the comment applies to the primary table.
But when on() is explicitly specified, the comment applies to the mapped table or column with the specified name.
For example:
```
 @Entity
 @Table(name = "book")
 @SecondaryTable(name = "edition")
 @Comment("The primary table for Book")
 @Comment(on = "edition",
          value = "The secondary table for Book")
 class Book { ... }
 
```
API Note:

In principle, it's possible for a column of a secondary table to have the same name as a column of the primary table, or as a column of some other secondary table. Therefore, on() may be ambiguous.

- Required Element Summary
  
  Required Elements
  Modifier and Type Required Element Description
  
  String value
  The text of the comment.
- Optional Element Summary
  
  Optional Elements
  Modifier and Type Optional Element Description
  
  String on
  The name of the table or column to add the comment to.

- Element Detail
  - value
```
String value
```
    The text of the comment.
- - on
```
String on
```
    The name of the table or column to add the comment to.
    
    Default:
    
    ""