in oss-20190517/src/main/java/com/aliyun/sdk/service/oss20190517/encryption/internal/CipherInputStream.java [92:100]
public long skip(long n) throws IOException {
int available = max_pos - curr_pos;
if (n > available)
n = available;
if (n < 0)
return 0;
curr_pos += n;
return n;
}