LOG.debug(getName() + ": has #" + call.id + " from " +
call.connection);
String errorClass = null;
String error = null;
Writable value = null;
CurCall.set(call);
UserGroupInformation previous = UserGroupInformation.getCurrentUGI();
UserGroupInformation.setCurrentUGI(call.connection.ticket);
try {
value = call(call.param, call.timestamp); // make the call
} catch (Throwable e) {
LOG.info(getName()+", call "+call+": error: " + e, e);
errorClass = e.getClass().getName();
error = StringUtils.stringifyException(e);
}
UserGroupInformation.setCurrentUGI(previous);
CurCall.set(null);
if (buf.size() > buffersize) {
// Allocate a new BAOS as reset only moves size back to zero but
// keeps the buffer of whatever the largest write was -- see
// hbase-900.
buf = new ByteArrayOutputStream(buffersize);
} else {
buf.reset();
}
DataOutputStream out = new DataOutputStream(buf);
out.writeInt(call.id); // write call id
out.writeBoolean(error != null); // write error flag
if (error == null) {
value.write(out);
} else {
WritableUtils.writeString(out, errorClass);
WritableUtils.writeString(out, error);
}
call.setResponse(ByteBuffer.wrap(buf.toByteArray()));