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Core components supporting the Micronaut Framework

There is a newer version: 4.7.9

/*
 * Copyright 2017-2021 original 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
 *
 * https://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 io.micronaut.core.annotation;

import jakarta.annotation.Nonnull;

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;



/**
 * A common  annotation to declare that annotated elements cannot be {@code null}. 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 Micronaut API.
 *
 * Should be used at parameter, return value, and field level. Method overrides should repeat parent {@code @NonNull} annotations unless
 * they behave differently.
 *
 * @author graemerocher
 * @see Nullable
 * @since 2.4
 */
@Target({ElementType.METHOD, ElementType.PARAMETER, ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.TYPE_PARAMETER, ElementType.TYPE_USE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Nonnull
public @interface NonNull {
    /**
     * Whether the nullable behaviour is inherited by subclasses or implementors in interfaces.
     * @return True if it should be inherited (defaults to false)
     * @since 4.1.0
     */
    boolean inherited() default false;
}