private boolean possibleFlush() throws java.io.IOException {
        if (buffers.size() > MAXBUFFERS) {
            flush();
            return true;
        }
        return false;
    }
Data store for AbstractByteWriter. Tested in unit tests for ByteWriter.

@author Steinar Knutsen
vespajlib/src/main/java/com/yahoo/io/BufferChain.java