short fieldId = reader.getFieldId();
ThriftCodec<?> codec = parameterCodecs.get(fieldId);
if (codec == null) {
// unknown field
reader.skipFieldData();
}
else {
// Map the incoming arguments to an array of arguments ordered as the java
// code for the handler method expects to see them
args[thriftParameterIdToJavaArgumentListPositionMap.get(fieldId)] = reader.readField(codec);