org.checkerframework.framework.qual.EnsuresQualifier Maven / Gradle / Ivy
package org.checkerframework.framework.qual;
import java.lang.annotation.Annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Repeatable;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* A postcondition annotation to indicate that a method ensures that certain expressions have a
* certain type qualifier once the method has successfully terminated. The expressions for which the
* qualifier holds after the method's execution are indicated by {@code expression} and are
* specified using a string. The qualifier is specified by the {@code qualifier} annotation element.
*
* Here is an example use:
*
*
* {@literal @}EnsuresQualifier(expression = "p.f1", qualifier = Odd.class)
* void oddF1_1() {
* p.f1 = null;
* }
*
*
* Some type systems have specialized versions of this annotation, such as {@code
* org.checkerframework.checker.nullness.qual.EnsuresNonNull} and {@code
* org.checkerframework.checker.lock.qual.EnsuresLockHeld}.
*
* @see EnsuresQualifierIf
* @checker_framework.manual #java-expressions-as-arguments Syntax of Java expressions
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.CONSTRUCTOR})
@InheritedAnnotation
@Repeatable(EnsuresQualifier.List.class)
public @interface EnsuresQualifier {
/**
* Returns the Java expressions for which the qualifier holds after successful method termination.
*
* @return the Java expressions for which the qualifier holds after successful method termination
* @checker_framework.manual #java-expressions-as-arguments Syntax of Java expressions
*/
String[] expression();
/**
* Returns the qualifier that is guaranteed to hold on successful termination of the method.
*
* @return the qualifier that is guaranteed to hold on successful termination of the method
*/
Class extends Annotation> qualifier();
/**
* A wrapper annotation that makes the {@link EnsuresQualifier} annotation repeatable.
*
* Programmers generally do not need to write this. It is created by Java when a programmer
* writes more than one {@link EnsuresQualifier} annotation at the same location.
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.CONSTRUCTOR})
@InheritedAnnotation
@interface List {
/**
* Return the repeatable annotations.
*
* @return the repeatable annotations
*/
EnsuresQualifier[] value();
}
}