类型的隐式转换在编码中需要特别的注意。今天遇到了一个bug

• 先做下测试

  @Test
    public void inttolongValue() {
        int tmp = 0x80000000;
        long value = (long)tmp;
        System.out.println(value);
        
    }

输出结果：-2147483648

* 这里   longToByteArray 的参数从int转为为了long，16进制输出内容，查看转换后每个字节具体内容

    public void inttolong() {
        System.out.println("0x80000000 , int          : " + ByteBufUtil.hexDump(intToByteArray(0x80000000)));
        System.out.println("0x80000000 convert to long: " + ByteBufUtil.hexDump(longToByteArray(0x80000000)));
    }

    public static byte[] longToByteArray(long i) {
        byte[] result = new byte[8];
        //由高位到低位
        result[0] = (byte)((i >> 56) & 0xFF);
        result[1] = (byte)((i >> 48) & 0xFF);
        result[2] = (byte)((i >> 42) & 0xFF);
        result[3] = (byte)((i >> 32) & 0xFF);
        result[4] = (byte)((i >> 24) & 0xFF);
        result[5] = (byte)((i >> 16) & 0xFF);
        result[6] = (byte)((i >> 8) & 0xFF);
        result[7] = (byte)(i & 0xFF);
        return result;
    }

运行结果：

0x80000000 , int          : 80000000
0x80000000 convert to long: ffffffff80000000

这里int 转为为long 后，高位全部补充为1，导致了问题