UTF8 is a better option than US-ASCII for the default encoding of PGStream

Hi,all
The problem I encountered is that,when lc_messages = 'ja_JP.UTF-8' is set
in postgresql.conf,and initial connection to database server failed(for
example:user name,password or dbname is misspelled),I see garbled error
message text in the client .The reason is that,in PGStream
constrcutor,default encoding of ASCII is
set(Encoding.getJVMEncoding("US-ASCII")).For the following reasons,maybe
UTF8 is a better option for default encoding.

1.When initializing connection ,jdbcclient send client_encoding parameter
as UTF-8
see
org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(HostSpec[],
String, String, Properties, Logger)

2. When initial connection to server completes,jdbc client only receive the
value for client_encoding as UTF-8
see
org.postgresql.core.v3.ConnectionFactoryImpl.readStartupMessages(PGStream,
ProtocolConnectionImpl, Logger)

if (name.equals("client_encoding"))
{
if (!value.equals("UTF8"))
throw new PSQLException(GT.tr("Protocol error.
Session setup failed."), PSQLState.PROTOCOL_VIOLATION);

pgStream.setEncoding(Encoding.getDatabaseEncoding("UTF8"));
}

So there seems no reason to initiate the encoding as US-ASCII.

Best regards.
Charles.