What is the purpose of the change?

see Resolving the Thread-Safety Problem in registerReferenceKeyAndBeanName Using an Overloaded computeIfAbsent #15219

org.apache.dubbo.config.spring.reference.ReferenceBeanManager.java

    public void registerReferenceKeyAndBeanName(String referenceKey, String referenceBeanNameOrAlias) {
        List<String> list =
                ConcurrentHashMapUtils.computeIfAbsent(referenceKeyMap, referenceKey, (key) -> new ArrayList<>());
        if (!list.contains(referenceBeanNameOrAlias)) {
            list.add(referenceBeanNameOrAlias);
            // register bean name as alias
            referenceAliasMap.put(referenceBeanNameOrAlias, list.get(0));
        }
    }

The ConcurrentHashMapUtils.computeIfAbsent method ensures the creation of a new list in a thread-safe manner when no list exists for the given referenceKey. However, the subsequent operations if (!list.contains(referenceBeanNameOrAlias)) and list.add(referenceBeanNameOrAlias) are not atomic. This situation can lead to thread-safety issues where multiple threads might simultaneously pass the contains check and then all perform the add operation, resulting in duplicate referenceBeanNameOrAlias entries within the list.

@AlbumenJ PTAL

Checklist

• Make sure there is a GitHub_issue field for the change.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit-test to verify your logic correction. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Make sure gitHub actions can pass. Why the workflow is failing and how to fix it?