org.springframework.lang

注释类型 Nullable

@Target(value={METHOD,PARAMETER,FIELD})
 @Retention(value=RUNTIME)
 @Documented
 @Nonnull(when=MAYBE)
 @TypeQualifierNickname
public @interface Nullable

A common Spring annotation to declare that annotated elements can be null under some circumstance.

Leverages JSR-305 meta-annotations to indicate nullability in Java to common tools with JSR-305 support and used by Kotlin to infer nullability of Spring API.

Should be used at parameter, return value, and field level. Methods override should repeat parent @Nullable annotations unless they behave differently.

Can be used in association with @NonNullApi or @NonNullFields to override the default non-nullable semantic to nullable.

从以下版本开始:

5.0

作者:

Sebastien Deleuze, Juergen Hoeller

另请参阅:

NonNullApi, NonNullFields, NonNull