package com.hisense.tiger.list; import java.util.ArrayList; import java.util.Iterator; import java.util.List; public class ListTest { public static void main(String[] args) { List<String> list = new ArrayList<String>(); long t1,t2; for(int j = 0; j < 10000000; j++) { list.add("aaaaaa" + j); } System.out.println("List first visit method:"); t1=System.currentTimeMillis(); for(String tmp:list) { //System.out.println(tmp); } t2=System.currentTimeMillis(); System.out.println("Run Time:" + (t2 -t1) + "(ms)"); System.out.println("List second visit method:"); t1=System.currentTimeMillis(); for(int i = 0; i < list.size(); i++) { list.get(i); //System.out.println(list.get(i)); } t2=System.currentTimeMillis(); System.out.println("Run Time:" + (t2 -t1) + "(ms)"); System.out.println("List Third visit method:"); Iterator<String> iter = list.iterator(); t1=System.currentTimeMillis(); while(iter.hasNext()) { iter.next(); //System.out.println(iter.next()); } t2=System.currentTimeMillis(); System.out.println("Run Time:" + (t2 -t1) + "(ms)"); System.out.println("Finished!!!!!!!!"); } } |