public byte receive() throws EdbcEx {
int msg_id;
if (trace.enabled(3)) trace.write(title + ": reading next message");
/*
** Check to see if message header is in the input
** buffer (handles message concatenation).
*/
while (in.avail() < 8) {
short tl_id;
/*
** Headers are not split across continued messages.
** Data remaining in the current buffer indicates
** a message processing error.
*/
if (in.avail() > 0) {
if (trace.enabled(1))
trace.write(title + ": invalid header length " + in.avail() + " bytes");
disconnect();
throw EdbcEx.get(E_IO0002_PROTOCOL_ERR);
}
try {
tl_id = in.receive();
} catch (EdbcEx ex) {
disconnect();
throw ex;
}
if (tl_id != JDBC_TL_DT) {
if (trace.enabled(1))
trace.write(title + ": invalid TL packet ID 0x" + Integer.toHexString(tl_id));
disconnect();
throw EdbcEx.get(E_IO0002_PROTOCOL_ERR);
}
}
/*
** Read and validate message header.
*/
if ((msg_id = in.readInt()) != JDBC_MSG_ID) {
if (trace.enabled(1))
trace.write(title + ": invalid header ID 0x" + Integer.toHexString(msg_id));
disconnect();
throw EdbcEx.get(E_IO0002_PROTOCOL_ERR);
}
in_msg_len = in.readShort();
in_msg_id = in.readByte();
in_msg_flg = in.readByte();
if (trace.enabled(2))
trace.write(
title
+ ": received message "
+ IdMap.map(in_msg_id, MsgConst.msgMap)
+ " length "
+ in_msg_len
+ ((in_msg_flg & JDBC_MSG_EOD) == 0 ? "" : " EOD")
+ ((in_msg_flg & JDBC_MSG_EOG) == 0 ? "" : " EOG"));
return (in_msg_id);
} // receive
