double readDouble


描述

所述java.io.DataInputStream.readDouble()方法读取8个字节,并返回一个双值。

声明

以下是java.io.DataInputStream.readDouble()方法的声明

public final double readDouble()

参数

NA

返回值

此方法返回8个字节的输入流,解释为double。

异常

IOException - 如果发生I / O错误或流已关闭。

EOFException - 如果流到达结尾。

实例

以下示例显示了java.io.DataInputStream.readDouble()方法的用法。

package com.tutorialspoint;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class DataInputStreamDemo {
   public static void main(String[] args) throws IOException {
      InputStream is = null;
      DataInputStream dis = null;
      FileOutputStream fos = null;
      DataOutputStream dos = null;
      double[] dbuf = {65.56,66.89,67.98,68.82,69.55,70.37};

      try {
         // create file output stream
         fos = new FileOutputStream("c:\\test.txt");

         // create data output stream
         dos = new DataOutputStream(fos);

         // for each byte in the buffer
         for (double d:dbuf) {

            // write double to the data output stream
            dos.writeDouble(d);         
         }

         // force bytes to the underlying stream
         dos.flush();

         // create file input stream
         is = new FileInputStream("c:\\test.txt");

         // create new data input stream
         dis = new DataInputStream(is);

         // read till end of the stream
         while(dis.available()>0) {

            // read character
            double c = dis.readDouble();

            // print
            System.out.print(c + " ");
         }

      } catch(Exception e) {
         // if any I/O error occurs
         e.printStackTrace();
      } finally {
         // releases all system resources from the streams
         if(is!=null)
            is.close();
         if(dos!=null)
            is.close();
         if(dis!=null)
            dis.close();
         if(fos!=null)
            fos.close();
      }
   }
}

让我们编译并运行上面的程序,这将产生以下结果

65.56 66.89 67.98 68.82 69.55 70.37