Package com.uber.nullaway.annotations

Annotation Type EnsuresNonNullIf

@Retention(CLASS)
@Target(METHOD)
public @interface EnsuresNonNullIf

An annotation describing a nullability post-condition for an instance method. Each parameter to the annotation should be a field of the enclosing class. The method must ensure that the method returns true in case the fields are non-null. The method can also return false in case the fields are non-null (inverse logic), and in such case, you must set result to false. NullAway verifies that the property holds.

Here is an example:

 class Foo {
     @Nullable Object theField;

     @EnsuresNonNullIf("theField", result=true) // "this.theField" is also valid
     boolean hasTheField() {
         return theField != null;
     }

     void bar() {
         if(!hasTheField()) {
             return;
         }

         // No error, NullAway knows theField is non-null after call to hasTheField()
         theField.toString();
     }
 }
 

Required Element Summary

Required Elements

Modifier and Type	Required Element	Description
java.lang.String[]	value	The list of fields that are non-null after the method returns the given result.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element	Description
boolean	result	The return value of the method under which the postcondition holds.

Element Detail

value

java.lang.String[] value

The list of fields that are non-null after the method returns the given result.

Returns:

The list of field names

result

boolean result

The return value of the method under which the postcondition holds. The default is set to true, which means the method should return true in case fields are non-null.

Returns:

true or false

Default:

true