public SendUsersMessageRequest withTraceId(String traceId) {
        setTraceId(traceId);
        return this;
    }
<p>
The unique identifier for tracing the message. This identifier is visible to message recipients.
</p>

@param traceId
       The unique identifier for tracing the message. This identifier is visible to message recipients.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-pinpoint/src/main/java/com/amazonaws/services/pinpoint/model/SendUsersMessageRequest.java