Java写100 000个随机双精度型的数到一个文件中

写100 000个随机双精度型的数到一个文件中

，写100 000个随机双精度型的数到一个文件中，同时测试运用缓冲和非缓冲技术进行这种操作所需要的时间。再做同样的试验来测试读100 000个双精度型数的操作。

import java.io.*;
public class WriteUnbufferedTest{
    public static void main(String args[]){
        try{
            long start = System.currentTimeMillis();
            FileOutputStream fs_out 
                =new FileOutputStream("sample.dat");
            DataOutputStream out = new DataOutputStream(fs_out);
            for (int i = 0; i < 10000000; i++)
                out.writeDouble(Math.random());
            out.close();
            long stop  = System.currentTimeMillis();
            System.out.println("Time passed: " + (stop - start));
        } catch(IOException ioe) {
             System.out.println(ioe); 
        }
    }
}

缓冲技术版
import java.io.*;
public class WriteBufferedTest{
public static void main(String args[]){
try{
long start = System.currentTimeMillis();
FileOutputStream fs_out
=new FileOutputStream(“sample.dat”);
BufferedOutputStream bfs_out
=new BufferedOutputStream(fs_out);
DataOutputStream out = new DataOutputStream(bfs_out);
for (int i = 0; i < 10000000; i++)
out.writeDouble(Math.random());
out.close();
long stop = System.currentTimeMillis();
System.out.println("Time passed: " + (stop - start));
}catch(IOException ioe) {
System.out.println(ioe);
}
}
}

了解本专栏 订阅专栏 解锁全文