vertx-db2-client return error codes when querying data with chinese characters

Question

Like picture above

Are there some options to control the encoding? (switch between UTF8 and GBK?)

I found a DEFAULT_CHARSET property(the value is utf8) in io.vertx.db2client.DB2ConnectOptions, but no code use it. Is there a way to pass custom charset to DB2ConnectOptions instance?

I tried to set charset directly in config file(the connect part will be parsed into a SqlConnectOptions instance), but it seems the client still use utf8

  connect:
    host: 192.168.0.100
    port: 50000
    database: test
    charset: GBK
    pipelined: true
    user: test
    password: test
  pool:
    name: test
    shared: true

result of select name,value from sysibmadm.dbcfg where name in ('codepage','codeset','territory','country'):

[
{
"NAME": "codepage",
"VALUE": "1386"
},
{
"NAME": "codeset",
"VALUE": "GBK"
},
{
"NAME": "country",
"VALUE": "86"
},
{
"NAME": "territory",
"VALUE": "CN"
}
]