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标题: 数据流对象DataInputStream、DataOutputStream的使用 [打印本页]

作者: jekeyhui99 时间: 2015-11-21 17:16
标题: 数据流对象DataInputStream、DataOutputStream的使用
数据流包括DataInputStream、DataOutputStream类，他们允许按照java的基础数据类型读写流中的数据。具体细节请查看java api；

public class DataOutputTest {

public static void main(String[] args) throws IOException {
  String username = "383065059";
  String path = "F:/workplaceT/Test/src/" + username;
  String inforTxt = "msg.db";
  File infoFile = new File(path + "/" + inforTxt);
  FileOutputStream fileOut = new FileOutputStream(infoFile);

  DataOutputStream out = new DataOutputStream(fileOut);
  //定义要保存的数据数组
  double[] prices={19.90,12.56,18.90,14.99,20.00};//长度5
  int[] amount={3,4,5,6,7,8};
  String[] descs={"java ee","java se","oracle","sqlserver","android"};
  //将prices，amount及descs中的数据以Tab键为分割保存到文件中。
  for(int i=0;i<5;i++){
out.writeDouble(prices);
out.writeChar('\t');

out.writeInt(amount);
out.writeChar('\t');

out.writeUTF(descs);
out.writeChar('\t');
  }
  out.close();

  //创建的数据输入流，将上面保存的文件再次打开并读取
  FileInputStream fileIn = new FileInputStream(infoFile);
  DataInputStream in=new DataInputStream(fileIn);
   double price;
   int amnt;
   String desc;
   double total=0.0;
   for(int i=0;i<5;i++){
   price=in.readDouble();
   in.readChar();//扔掉tab
   amnt=in.readInt();
   in.readChar();
   desc=in.readUTF();
   in.readChar();
   System.out.println("你订购了 "+amnt+"件 "+desc+",价格为 "+price);
   total=total+amnt*price;
   }
   System.out.println("共计金额："+total+"元");
   in.close();
}

}

//读写为互逆操作，规律比较死。

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