今天无聊测试了下DataOutputStream和FileWriter的性能,惊奇的发现FileWriter的性能比DataOutputStream的高很多倍啊,看了下源代码FileWriter里面也是构造了一个FileOutputStream,而我也是用FileOutputStream构造的DataOutputStream的啊,呵呵!
知道的高手了讨论下,我对java底层不是太了解。
测试代码如下:
import java.io.*; public class FileTester { private DataOutputStream os; private FileWriter fw; public void test() throws IOException { os = new DataOutputStream(new FileOutputStream("D://test1.txt")); long time1 = System.currentTimeMillis(); for (int i = 0; i < 1000000; i++) { os.write("测试测试测试测试/n".getBytes()); } os.flush(); os.close(); long time2 = System.currentTimeMillis(); fw = new FileWriter(new File("D://test3.txt")); for (int i = 0; i < 1000000; i++) { fw.write("测试测试测试测试/n"); } fw.flush(); fw.close(); long time3 = System.currentTimeMillis(); System.out.println("time1:" + (time2 - time1)); System.out.println("time2:" + (time3 - time2)); } public static void main(String[] args) throws IOException { FileTester f = new FileTester(); f.test(); } }
测试结果:
time1:8390
time2:1000
测试环境:windows Xp + Eclipse + jdk5