**[Sam Brannen](https://jira.spring.io/secure/ViewProfile.jspa?name=sbrannen)** opened **[SPR-13060](https://jira.spring.io/browse/SPR-13060?redirect=false)** and commented `java.util.Map` introduces `putIfAbsent(K, V)` in Java 8. Thus, the goal of this issue is to provide the same convenience to users of `AnnotationAttributes` before Spring requires Java 8. --- **Referenced from:** commits https://github.com/spring-projects/spring-framework/commit/ca09b1ff200280c885bca7a4191711e7a21e62de