我设置了getchars()调用的测试示例，并且字节按顺序返回1。
byte [] readBufA = new byte [] {1,2,3,4,5,6,7}; // Test array
然后我运行getchar，结果是1。
String strIncom = new String(readBufA, 0, 7); // create string from bytes array
String strIncom = new String(readBuf, 0, msg.arg1); // create string from bytes array
sb.append(strIncom); // append string
int counter = sb.length(); // Get length of string
if (counter == 7){
getChars(0,7,readBufA,0);
Log.d(TAG, "Data " + sb + " Size " + (char)readBuf[0] + " " + (char)readBuf[1] +
" " + (char)readBuf[2] + " " + (char)readBuf[3] + " " +(char)readBuf[4] +
" " + (char)readBuf[5] + " " + (char)readBuf[6] +" " + (char)readBuf[7]+ " " + counter); // receive massage
log.d返回（2,3,4,5,6,7， - ， - ，7）计数器是正确的，但没有看到正确的回报