PrintWriter(三种使用方式效率对比)——单位(纳秒)

应学生【弓先生】需求，做此测试，得到帮助的同志心里要谢谢【弓先生】。

//第一种
PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
//第二种
PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));
//第三种
PrintWriter pw = new PrintWriter(System.out);

三种方式时间对比

第一次对比：count=100

第二次对比：count=10000

两次对比结果

第三次：十万对比

1、PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

package test;

import java.io.BufferedWriter;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

public class demo {
	public static void main(String[] args) {
		int count=100;
		long start = System.nanoTime();
		PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
		for (int i = 0; i < count; i++) {
			pw.println(i);
		}
		long end = System.nanoTime();
		pw.println("累计"+count+"的值用时："+(end-start)+"纳秒");
		pw.close();
	}
}

2、PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));

package test;

import java.io.OutputStreamWriter;
import java.io.PrintWriter;

public class demo {
	public static void main(String[] args) {
		int count = 100;
		long start = System.nanoTime();
		PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));
		for (int i = 0; i < count; i++) {
			pw.println(i);
		}
		long end = System.nanoTime();
		pw.println("累计" + count + "的值用时：" + (end - start) + "纳秒");
		pw.close();
	}
}

3、PrintWriter pw = new PrintWriter(System.out);

package test;

import java.io.PrintWriter;

public class demo {
	public static void main(String[] args) {
		int count = 100;
		long start = System.nanoTime();
		PrintWriter pw = new PrintWriter(System.out);
		for (int i = 0; i < count; i++) {
			pw.println(i);
		}
		long end = System.nanoTime();
		pw.println("累计" + count + "的值用时：" + (end - start) + "纳秒");
		pw.close();
	}
}