/*
* Copyright 2002-2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.lang;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import javax.annotation.Nonnull;
import javax.annotation.meta.TypeQualifierNickname;
import javax.annotation.meta.When;
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.
Author: Sebastien Deleuze, Juergen Hoeller See Also: Since: 5.0
/**
* A common Spring annotation to declare that annotated elements can be {@code 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.
*
* <p>Should be used at parameter, return value, and field level. Methods override should
* repeat parent {@code @Nullable} annotations unless they behave differently.
*
* <p>Can be used in association with {@code @NonNullApi} or {@code @NonNullFields} to
* override the default non-nullable semantic to nullable.
*
* @author Sebastien Deleuze
* @author Juergen Hoeller
* @since 5.0
* @see NonNullApi
* @see NonNullFields
* @see NonNull
*/
@Target({ElementType.METHOD, ElementType.PARAMETER, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Nonnull(when = When.MAYBE)
@TypeQualifierNickname
public @interface Nullable {
}