javax.annotation.Nonnegative Maven / Gradle / Ivy
package javax.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import javax.annotation.meta.TypeQualifier;
import javax.annotation.meta.TypeQualifierValidator;
import javax.annotation.meta.When;
/**
* This annotation is used to annotate a value that should only contain nonnegative values.
*
* When this annotation is applied to a method it applies to the method return value.
*/
@Documented
@TypeQualifier(applicableTo = Number.class)
@Retention(RetentionPolicy.RUNTIME)
public @interface Nonnegative {
When when() default When.ALWAYS;
class Checker implements TypeQualifierValidator {
public When forConstantValue(Nonnegative annotation, Object v) {
if (!(v instanceof Number))
return When.NEVER;
boolean isNegative;
Number value = (Number) v;
if (value instanceof Long)
isNegative = value.longValue() < 0;
else if (value instanceof Double)
isNegative = value.doubleValue() < 0;
else if (value instanceof Float)
isNegative = value.floatValue() < 0;
else
isNegative = value.intValue() < 0;
if (isNegative)
return When.NEVER;
else
return When.ALWAYS;
}
}
}