###### 问题遇到的现象和发生背景
在使用mybatis-plus和Dubbo时 出现com.alibaba.com.caucho.hessian.io.MapDeserializer@439012f6 错误提示
//第一种方法会出错
``` boolean result = couponService.update(new UpdateWrapper().eq("coupon_id", order.getCouponId()).set("is_used", 1));
//第二种方法不会出错
``` boolean result = couponService.updateById(coupon);
###### 运行结果及报错内容
ava.lang.UnsupportedOperationException: com.alibaba.com.caucho.hessian.io.MapDeserializer@439012f6
at com.alibaba.com.caucho.hessian.io.AbstractDeserializer.readLengthList(AbstractDeserializer.java:92)
at com.alibaba.com.caucho.hessian.io.AbstractDeserializer.readLengthList(AbstractDeserializer.java:98)
at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2233)
at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2104)
at org.apache.dubbo.common.serialize.hessian2.Hessian2ObjectInput.readObject(Hessian2ObjectInput.java:102)
at org.apache.dubbo.common.serialize.ObjectInput.readAttachments(ObjectInput.java:87)
at org.apache.dubbo.rpc.protocol.dubbo.DecodeableRpcInvocation.decode(DecodeableRpcInvocation.java:165)
at org.apache.dubbo.rpc.protocol.dubbo.DecodeableRpcInvocation.decode(DecodeableRpcInvocation.java:83)
at org.apache.dubbo.remoting.transport.DecodeHandler.decode(DecodeHandler.java:57)
at org.apache.dubbo.remoting.transport.DecodeHandler.received(DecodeHandler.java:44)
at org.apache.dubbo.remoting.transport.dispatcher.ChannelEventRunnable.run(ChannelEventRunnable.java:57)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.dubbo.common.threadlocal.InternalRunnable.run(InternalRunnable.java:41)
at java.lang.Thread.run(Thread.java:748)
###### 我的解答思路和尝试过的方法
###### 我想要达到的结果
第一种办法有办法解决嘛
