ProtoBuilderReturnValueIgnored
Unnecessary call to proto's #build() method. If you don't consume the return value of #build(), the result is discarded and the only effect is to verify that all required fields are set, which can be expressed more directly with #isInitialized().
Suppression
Suppress false positives by adding the suppression annotation @SuppressWarnings("ProtoBuilderReturnValueIgnored") to the enclosing element.