简单的数据写入（质数写入文件）

最新推荐文章于 2023-05-05 15:03:18 发布

原创最新推荐文章于 2023-05-05 15:03:18 发布 · 508 阅读

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#import #dos #null #string #class

打开文件，发现会是乱码，主要是因为字节数据

package com.sun.print;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.EOFException;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class WritePrime {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
writePrime();
}

/*static void readPrimes() {
  DataInputStream dis = null;
  try {
   dis = new DataInputStream(new FileInputStream("d://prime.txt"));
   try {
    while (true) {
     int val = dis.readInt();
     System.out.println(val);
    }
   } catch (EOFException ex) {

}

  } catch (IOException ex) {
   ex.printStackTrace();
  }
}
*/
static void writePrime() {
  DataOutputStream dos = null;
  try {
   dos = new DataOutputStream(new FileOutputStream("d://aa.txt"));
   for (int i = 1; i <= 1000; i++) {
    if (isPrime(i))
     dos.writeInt(i);
   }
   System.out.println("write over !");
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } finally {
   try {
    if (dos != null)
     dos.close();
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }

}

private static boolean isPrime(int n) {
  // TODO Auto-generated method stub
  for (int i = 2; i <= n / 2; i++)
   if (n % i == 0)
    return false;
  return true;

}
}