在 Java 中使用 ByteBuffer 处理交错读/写的最佳方法是什么？

Question

Edited: to make the question less 'opinion-based'

I want to ask for the suggestible way of using bytebuffer in the case of interleaved read/write.

My program processes a random sequence of NIO that performs read() and write() operation to a ByteBuffer . Currently I use a variable to record whether the last operation was read() or write() , and call flip() or compact() accordingly.

Is this the best approach or ByteBuffer is not meant to handle this task?

---

Original question title: Is Java ByteBuffer poorly designed?

I just started with Java NIO and I think the Bytebuffer is designed in a way that makes interleaved read/write operations difficult to achieve. Where such operation pattern is exactly the reason why we have a "buffer" in NIO.

Specifically, the flip() and compact() is unnecessary details for programming. If I have a random sequence of read() and write() to a bytebuffer, then I have not choice but to keep a separate variable to track whether the buffer has been 'flipped'. For example, for a flipped buffer I need to compact() it before write again, but I cannot do so for an unflipped buffer.

IMO, there is almost no case that a write() following read() do no need to call compact() or clear() first. Also, no read() after write() is without flip() , so I think either should be done:

• make 'read mode' and 'write mode' explicit and throw warning if write in read mode or vice versa. Use a explicit readMode() or writeMode() command to switch.
• remove the need to flip/compact before read/write by either adopt a different design (eg circular buffer) or by making it implicit in read/write.

As I am still quite new to Java, I want to know if my complaint is legit or there is some careful design choice going on in implementing Bytebuffer?

Answer 1

Many thanks to user207421 for answering. He proposed a wonderful solution which I am adopting in my design now.

Basically, you always keep the ByteBuffer in the same state after each operation.

For example, to keep the ByteBuffer in unflipped state, then every write() operation should be wrapped with flip() and compact() before and after. Also, Add synchronization to deal with threads.