counttime.java

FileWriter与BufferedWriter的一个对比小程序。可以在程序中看到两种写文件方式在速度上的不同

package Prob_1;

import java.io.*;

public class CountTime {

	/**
	 * @param args
	 */
	public static void main(String[] args) 
	throws IOException{
		// TODO Auto-generated method stub
		long begin = 0;
		long current = 0;
		long num = 1000000;
		
		String fileName1 = "wr.txt";
		String fileName2 = "bwr.txt";
		FileWriter wr = new FileWriter( fileName1 );
		BufferedWriter bwr = new BufferedWriter( new FileWriter( fileName2 ) );
		
		begin = System.currentTimeMillis();
		for( int i=0; i<= num; i++ )
			{
			wr.write("Hello!\n");
			}
		current = System.currentTimeMillis();
		System.out.println( "FileWriter:" + (current-begin) + "ms" );
		
		begin = System.currentTimeMillis();
		for( int i=0; i<= num; i++ )
			bwr.write("Hello!\n");
		current = System.currentTimeMillis();
		System.out.println( "BufferedFileWriter:" + (current-begin) + "ms" );		
	}

}