org.checkerframework.framework.qual

Annotation Type EnsuresQualifierIf

@Documented
 @Retention(value=RUNTIME)
 @Target(value=METHOD)
 @InheritedAnnotation
 @Repeatable(value=EnsuresQualifiersIf.class)
public @interface EnsuresQualifierIf

A conditional postcondition annotation to indicate that a method ensures that certain expressions have a certain qualifier once the method has finished, and if the result is as indicated by result. The expressions for which the annotation must hold after the method's execution are indicated by expression and are specified using a string. The qualifier is specified by the qualifier annotation argument.

Here is an example use:

    @EnsuresQualifierIf(result = true, expression = "#1", qualifier = Odd.class)
    boolean isOdd(final int p1, int p2) {
        return p1 % 2 == 1;
    }
 

This annotation is only applicable to methods with a boolean return type.

Some type systems have specialized versions of this annotation, such as org.checkerframework.checker.nullness.qual.EnsuresNonNullIf and org.checkerframework.checker.lock.qual.EnsuresLockHeldIf.

See Also:

EnsuresQualifier

See the Checker Framework Manual:

Syntax of Java expressions

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
String[]	expression The Java expressions for which the qualifier holds if the method terminates with return value result().
Class<? extends Annotation>	qualifier The qualifier that is guaranteed to hold if the method terminates with return value result().
boolean	result The return value of the method that needs to hold for the postcondition to hold.

Element Detail

expression

public abstract String[] expression

The Java expressions for which the qualifier holds if the method terminates with return value result().

See the Checker Framework Manual:

Syntax of Java expressions

qualifier

public abstract Class<? extends Annotation> qualifier

The qualifier that is guaranteed to hold if the method terminates with return value result().

result

public abstract boolean result

The return value of the method that needs to hold for the postcondition to hold.