private void postReceiveMessage(
final FetchRequest request, final MessageIterator it, final Partition partition) {
// 如果offset仍然没有前进，递增重试次数
if (it.getOffset() == 0) {
request.incrementRetriesAndGet();
} else {
request.resetRetries();
}
// 非自动ack模式
if (!partition.isAutoAck()) {
// 如果是回滚,则回滚offset，再次发起请求
if (partition.isRollback()) {
request.rollbackOffset();
partition.reset();
this.addRequst(request);
}
// 如果提交，则更新临时offset到存储
else if (partition.isAcked()) {
partition.reset();
this.ackRequest(request, it, true);
} else {
// 都不是，递增临时offset
this.ackRequest(request, it, false);
}
} else {
// 自动ack模式
this.ackRequest(request, it, true);
}
}
/**
* 返回是否需要跳过后续的处理
*
* @param request
* @param it
* @param listener
* @param partition
* @return
*/
private boolean processReceiveMessage(
final FetchRequest request,
final MessageIterator it,
final MessageListener listener,
final Partition partition) {
int count = 0;
while (it.hasNext()) {
final int prevOffset = it.getOffset();
try {
final Message msg = it.next();
MessageAccessor.setPartition(msg, partition);
if (((SimpleMessageConsumer) consumer).canConsumer(msg)) listener.recieveMessages(msg);
if (partition.isAutoAck()) {
count++;
} else {
// 提交或者回滚都必须跳出循环
if (partition.isAcked()) {
count++;
break;
} else if (partition.isRollback()) {
break;
} else {
// 不是提交也不是回滚，仅递增计数
count++;
}
}
} catch (final InvalidMessageException e) {
MetaStatLog.addStat(null, StatConstants.INVALID_MSG_STAT, request.getTopic());
// 消息体非法，获取有效offset，重新发起查询
this.getOffsetAddRequest(request, e);
return true;
} catch (final Throwable e) {
// 将指针移到上一条消息
it.setOffset(prevOffset);
log.error(
"MessageListener处理消息异常,topic="
+ request.getTopic()
+ ",partition="
+ request.getPartition(),
e);
// 跳出循环，处理消息异常，到此为止
break;
}
}
MetaStatLog.addStatValue2(null, StatConstants.GET_MSG_COUNT_STAT, request.getTopic(), count);
return false;
}