io.netty.handler.codec.http.multipart.HttpPostRequestDecoder$ErrorDataDecoderException: Bad string invalid escape sequence

When the http content contains the char % ,io.netty.handler.codec.http.QueryStringDecoder.decodeComponent() will throw a IllegalArgumentException with message: invalid escape sequence `%" .......

Does that mean that the http content cannot contain the char %? The request param is json str:

{"discountRate":"10%"}

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