java io流 数据流传输

//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);

    }
}