访问示例/demo/save接口直接报错

[baixu19900206]

There was an unexpected error (type=Internal Server Error, status=500).
status 500 reading Demo2Client#save(); content: {"timestamp":1535681660249,"status":500,"error":"Internal Server Error","exception":"java.lang.reflect.UndeclaredThrowableException","message":"No message available","path":"/demo/save"}