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Apache Dubbo Component

Java SDK (apache/dubbo)

Dubbo Version

Component Affected
dubbo-common

Environment Details
Dubbo version: 3.3.4-SNAPSHOT
JDK version: 17
Operating System: Windows 10

Steps to reproduce this issue

Steps to Reproduce
Call the method:
String result = StringUtils.toCommaDelimitedString(null, (String) null);

What you expected to happen

Expected Behavior
According to the method’s documentation, if either one or others is null, the method should return null. This behavior is expected to prevent invalid string construction from null values.

Actual Behavior
Instead of returning null, the method constructs a string: "null,null", which leads to unexpected results and causes a unit test failure in StringUtilsTest.
expected: <null> but was: <null,null>

Are you willing to submit a pull request to fix on your own?

• Yes I am willing to submit a pull request on my own!

Code of Conduct

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