UpdateTimestamp (Hibernate Javadocs)

```
@Retention(RUNTIME)
@Target({FIELD,METHOD})
public @interface UpdateTimestamp
```
Specifies that the annotated field of property is a generated update timestamp. The timestamp is regenerated every time an entity instance is updated in the database.
By default, the timestamp is generated in memory, but this may be changed by explicitly specifying the source(). Otherwise, this annotation is a synonym for @CurrentTimestamp(source=VM).

See Also:

CurrentTimestamp

- Optional Element Summary
  
  Optional Elements
  Modifier and Type Optional Element Description
  
  SourceType source
  Specifies how the timestamp is generated.

- Element Detail
  - source
```
SourceType source
```
    Specifies how the timestamp is generated. By default, it is generated in memory, which saves a round trip to the database.
    
    Default:
    
    org.hibernate.annotations.SourceType.VM