@NotNull @NotEmpty @NotBlank区别

@interface NotNull

The annotated element must not be {@code null}.
Accepts any type.
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@interface NotEmpty

* The annotated element must not be {@code null} nor empty. Supported types are:
* <ul>
* <li>{@code CharSequence} (length of character sequence is evaluated)</li>
* <li>{@code Collection} (collection size is evaluated)</li>
* <li>{@code Map} (map size is evaluated)</li>
* <li>Array (array length is evaluated)</li>
* </ul>
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@interface NotBlank

* The annotated element must not be {@code null} and must contain at least one
* non-whitespace character. Accepts {@code CharSequence}.