org.checkerframework.framework.util.QualifierKindHierarchy Maven / Gradle / Ivy
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package org.checkerframework.framework.util;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.checkerframework.checker.signature.qual.CanonicalName;
import org.checkerframework.framework.qual.AnnotatedFor;
import org.checkerframework.framework.type.ElementQualifierHierarchy;
import org.checkerframework.framework.type.MostlyNoElementQualifierHierarchy;
import org.checkerframework.framework.type.NoElementQualifierHierarchy;
import org.checkerframework.javacutil.TypeSystemError;
import java.lang.annotation.Annotation;
import java.util.List;
import java.util.Set;
import javax.lang.model.element.AnnotationMirror;
/**
* This interface holds information about the subtyping relationships between kinds of qualifiers. A
* "kind" of qualifier is its annotation class and is represented by the {@link QualifierKind}
* class. If a type system has more than one hierarchy, information about all hierarchies is stored
* in this class.
*
* The qualifier kind subtyping relationship may be an over-approximation of the qualifier
* subtyping relationship, for qualifiers that have elements/arguments. In other words, if a
* qualifier kind is a subtype of another qualifier kind, then qualifiers of those kinds may or may
* not be subtypes, depending on the values of any elements of the qualifiers. If qualifier kinds
* are not subtypes, then qualifiers of those kinds are never subtypes.
*
*
This interface is used by {@link NoElementQualifierHierarchy} and {@link
* ElementQualifierHierarchy} (but not {@link MostlyNoElementQualifierHierarchy}) to
* implement methods that compare {@link javax.lang.model.element.AnnotationMirror}s, such as {@link
* org.checkerframework.framework.type.QualifierHierarchy#isSubtypeShallow(AnnotationMirror,
* TypeMirror, AnnotationMirror, TypeMirror)}.
*
* @see DefaultQualifierKindHierarchy
* @see org.checkerframework.framework.util.DefaultQualifierKindHierarchy.DefaultQualifierKind
*/
@AnnotatedFor("nullness")
public interface QualifierKindHierarchy {
/**
* Returns the qualifier kinds that are the top qualifier in their hierarchies.
*
* @return the qualifier kinds that are the top qualifier in their hierarchies
*/
Set extends QualifierKind> getTops();
/**
* Returns the qualifier kinds that are the bottom qualifier in their hierarchies.
*
* @return the qualifier kinds that are the bottom qualifier in their hierarchies
*/
Set extends QualifierKind> getBottoms();
/**
* Returns the least upper bound of {@code q1} and {@code q2}, or {@code null} if the qualifier
* kinds are not in the same hierarchy. Ignores elements/arguments (as QualifierKind always
* does).
*
* @param q1 a qualifier kind
* @param q2 a qualifier kind
* @return the least upper bound of {@code q1} and {@code q2}, or {@code null} if the qualifier
* kinds are not in the same hierarchy
*/
@Nullable QualifierKind leastUpperBound(QualifierKind q1, QualifierKind q2);
/**
* Returns the greatest lower bound of {@code q1} and {@code q2}, or {@code null} if the
* qualifier kinds are not in the same hierarchy. Ignores elements/arguments (as QualifierKind
* always does).
*
* @param q1 a qualifier kind
* @param q2 a qualifier kind
* @return the greatest lower bound of {@code q1} and {@code q2}, or {@code null} if the
* qualifier kinds are not in the same hierarchy
*/
@Nullable QualifierKind greatestLowerBound(QualifierKind q1, QualifierKind q2);
/**
* Returns a list of all {@link QualifierKind}s sorted in ascending order.
*
* @return a list of all {@link QualifierKind}s sorted in ascending order
*/
List extends QualifierKind> allQualifierKinds();
/**
* Returns the {@link QualifierKind} for the given annotation class name. Throws an exception if
* one does not exist.
*
* @param name canonical name of an annotation class
* @return the {@link QualifierKind} for the given annotation class name
*/
QualifierKind getQualifierKind(@CanonicalName String name);
/**
* Returns the canonical name of {@code clazz}. Throws a {@link TypeSystemError} if {@code
* clazz} is anonymous or otherwise does not have a name.
*
* @param clazz annotation class
* @return the canonical name of {@code clazz}
*/
static @CanonicalName String annotationClassName(Class extends Annotation> clazz) {
String name = clazz.getCanonicalName();
if (name == null) {
throw new TypeSystemError("Qualifier classes must not be anonymous.");
}
return name;
}
}