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nio - 使用java7的AIO异步读取数据时发现有重复读取的现象

使用如下代码读取socket channel中的数据到缓冲区中,程序对读取到的数据进行处理。
如果读取到的一批数据中,存在半个message的情况下,程序会将本次剩余的半个message数据保存起来,
等下次读取到数据后,进行合并,然后判断程序是否能正常执行,若不能则表示第二次读取到的数据与
之前保存起来的半个message数据不是同一批,则程序继续重新处理第二次读取到的数据,然后第三次读取
后再合并,再试着处理...直到合并后能成功处理。

现在发现,合并后能成功处理,但是后面仍然会读取到已经处理过的半个消息的后半段数据,不知道各位大侠
有没有遇见过这种情况?

socket.read(byteBuffer, null, new CompletionHandler<Integer, Void>() {
    @Override
    public void completed(Integer result, Void attachment) {
        if(result==-1){
            close();
            return;
        }
        byteBuffer.clear();
        if (result > 0) {
            byteBuffer.limit(result);
            LOG.debug("server socket [{}] get " + result + " data from client:{}", clientIdentifier, getString(byteBuffer, result));
            if (!connectted) {
                handleConnect();
            } else {
                if (remainingData != null) {
                    combineBuffer();
                }
                
                while (byteBuffer.position() < result) {
                    doProcess();
                }
            }
        }
        byteBuffer.clear();
        socket.read(byteBuffer, null, this);
    }

    @Override
    public void failed(Throwable exc, Void attachment) {
        LOG.error("Server socket [{}] read failed,{}.", clientIdentifier, exc.toString());
        close();
    }
});
伊谢尔伦伊谢尔伦2765 days ago446

reply all(1)I'll reply

  • ringa_lee

    ringa_lee2017-04-17 15:06:56

    Another problem is that the number of bytes read each time is different. My message size is set to 2kb. Normally, every time the client sends a message, the server will read to 2kb. The data, but occasionally it only reads to 1kb or a few hundred bytes. Does anyone know what is going on?

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