buffered.java

java缓冲技术程序例子

//c19:Buffered.java
//author:ZhangHongbin 
//This program is protected by copyright laws.
//Compare Buffered and Unbuffered files.
import java.io.*;
import java.util.*;
public class Buffered
{
	public static void main(String[] args)throws Exception
	{
		FileWriter unbuff1 =new FileWriter("unbuff1.txt");
		BufferedWriter buff2 =new BufferedWriter(
			new FileWriter("buff2.txt"));
		BufferedWriter buff3 =new BufferedWriter(new BufferedWriter(
			new BufferedWriter(new BufferedWriter(new BufferedWriter(      
			new FileWriter("buff3.txt"))))));
		System.out.println("write unbuffered file1 "+
		timeCosted(unbuff1)+"ms");
		System.out.println("write buffered file2 "+
		timeCosted(buff2)+"ms");
		System.out.println("write buffered file3 "+
		timeCosted(buff3)+"ms");
 	}
	static long timeCosted(Writer out) throws Exception
	{
		System.out.println();
		Date startDate=new Date();
		for (int i=0;i<10000;i++)
		{
			out.write("O");
		}
		out.close();
		Date endDate=new Date();
		long timeLasted=endDate.getTime()-startDate.getTime();
		return timeLasted; 
	}
		
}