package org.checkerframework.checker.nullness.qual;
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 org.checkerframework.framework.qual.PolymorphicQualifier;
/**
* A polymorphic qualifier for the non-null type system.
*
* <p>Any method written using {@link PolyNull} conceptually has two versions: one in which every
* instance of {@link PolyNull} has been replaced by {@link
* org.checkerframework.checker.nullness.qual.NonNull}, and one in which every instance of {@link
* PolyNull} has been replaced by {@link org.checkerframework.checker.nullness.qual.Nullable}.
*
* @checker_framework.manual #nullness-checker Nullness Checker
* @checker_framework.manual #qualifier-polymorphism Qualifier polymorphism
*/
@Documented
@PolymorphicQualifier(Nullable.class)
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE_USE, ElementType.TYPE_PARAMETER})
public @interface PolyNull {}