//数据流传输import java.io.*;public class Index{    public static void main(String[] args) throws Exception{                //把这段当公式用就可以了        //不用记忆        ByteArrayOutputStream zjszl = new ByteArrayOutputStream();        DataOutputStream sjl = new DataOutputStream(zjszl);                long aa = 123456789;        sjl.writeLong(aa);                byte[] zjsz = zjszl.toByteArray();        ByteArrayInputStream srl = new ByteArrayInputStream(zjsz);        DataInputStream sjsr = new DataInputStream(srl);                long ss;        ss = sjsr.readLong();                System.out.println("ss="+ss);    }}