1# ArkTS Subsystem Changelog
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3## cl.arkts.1 Access Level of APIs of RestrictedWorker in the worker Module Changed
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5**Access Level**
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7Public API
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9**Reason for Change**
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11Due to security compliance requirements, the APIs of the **RestrictedWorker** class are changed from public APIs to system APIs.
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13**Change Impact**
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15This change is a non-compatible change.
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17Before change:
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19APIs of the **RestrictedWorker** class in the worker module are public APIs and can be called by third-party applications.
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21After change:
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23APIs of the **RestrictedWorker** class in the worker module are changed to system APIs and can be called only by system applications. When a non-system application uses these APIs, the compilation may fail.
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25**Start API Level**
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2711
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29**Change Since**
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31OpenHarmony SDK 5.0.0.44
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33**Key API/Component Changes**
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35Two APIs in the worker module:
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371. class RestrictedWorker extends ThreadWorker;
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392. constructor(scriptURL: string, options?: WorkerOptions);
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41**Adaptation Guide**
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43If only inter-thread communication is involved, you can use the **worker.ThreadWorker** class to create Worker threads.
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