JAVA LIST的三种遍历方法

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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!!!!!!!!");}}

转自http://blog.csdn.net/jkh753/article/details/11651599

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