If you try to set or get any extendedOptions for ServerSocket, will throw "UnsupportedOperationException". the root cause is below code in PlainSocketImpl.java
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if (getSocket() == null) {
throw new UnsupportedOperationException("unsupported option");
}
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getSocket() will always return null in case of serverSocket.
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if (getSocket() == null) {
throw new UnsupportedOperationException("unsupported option");
}
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getSocket() will always return null in case of serverSocket.