@Target(value={FIELD,METHOD,PARAMETER,LOCAL_VARIABLE})
 @Retention(value=CLASS)
 @Documented
public @interface NonNull

If put on a parameter, lombok will insert a null-check at the start of the method / constructor's body, throwing a NullPointerException with the parameter's name as message. If put on a field, any generated method assigning a value to this field will also produce these nullchecks.

Note that any annotation named NonNull with any casing and any package will result in nullchecks produced for generated methods (and the annotation will be copied to the getter return type and any parameters of generated methods), but only this annotation, if present on a parameter, will result in a null check inserted into your otherwise handwritten method. WARNING: If the java community ever does decide on supporting a single @NonNull annotation (for example via JSR305), then this annotation will be deleted from the lombok package. If the need to update an import statement scares you, you should use your own annotation named @NonNull instead of this one.