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比較Java數(shù)組和各種List的性能小結(jié)

更新時間：2016年08月28日 08:45:10 投稿：daisy

這篇文章主要是分別對Java數(shù)組、ArrayList、LinkedList和Vector進行隨機訪問和迭代等操作，并比較這種集合的性能。有需要的可以參考借鑒。

話不多說，直接看示例代碼

package cn.lion.test;
public class PerformanceTest {
   
   privatestatic final int SIZE =100000;
   publicstatic abstract class Test{
     privateString operation;
     publicTest(String operation){
       this.operation= operation;
     }
     publicabstract void test(List<String> list);
     publicString getOperation(){
       returnoperation;
     }
   }
   //執(zhí)行迭代操作的匿名類
   staticTest iterateTest = new Test("iterate"){
     publicvoid test(List<String> list){
       for(inti=0; i<10; i++){
          Iterator<String>it = list.iterator();
          while(it.hasNext()){
            it.next();
          }
       }
     }
   };
   //執(zhí)行隨機訪問的匿名類
   staticTest getTest = new Test("get"){
     publicvoid test(List<String> list){
       for(inti=0; i<list.size(); i++){
          for(intk=0; k<10; k++){
            list.get(k);
          }
       }
     }
   };
   //執(zhí)行插入的匿名類
   staticTest insertTest = new Test("insert"){
     publicvoid test(List<String> list){
       ListIterator<String>it = list.listIterator(list.size()/2);
       for(inti=0; i<SIZE; i++){
          it.add("lion");
       }
     }
   };
   //執(zhí)行刪除的匿名類
   staticTest removeTest = new Test("remove"){
     publicvoid test(List<String> list){
       ListIterator<String>it = list.listIterator();
       while(it.hasNext()){
          it.next();
          it.remove();
       }
     }
   };
   staticpublic void testArray(List<String> list){
     Test[]tests = {iterateTest, getTest};
     test(tests,list);
   }
   staticpublic void testList(List<String> list){
     Test[]tests = {insertTest, iterateTest, getTest, removeTest};
     test(tests,list);
   }
   staticpublic void test(Test[] tests, List<String> list){
     for(inti=0; i<tests.length; i++){
       System.out.print(tests[i].getOperation()+ "操作：");
       longt1 = System.currentTimeMillis();
       tests[i].test(list);
       longt2 = System.currentTimeMillis();
       System.out.print(t2-t1+ "ms");
       System.out.println();
     }
   }
   publicstatic void main(String[] args){
     
     List<String>list = null;
     //測試數(shù)組的迭代和隨機訪問操作
     System.out.println("------測試數(shù)組------");
     String[]tstr = new String[SIZE];
     Arrays.fill(tstr,"lion");
     list= Arrays.asList(tstr);
     testArray(list);
     
     tstr= new String[SIZE/2];
     Collection<String>coll = Arrays.asList(tstr);
     
     //測試Vector
     System.out.println("------測試Vector------");
     list= new Vector<String>();
     list.addAll(coll);
     testList(list);
     
     //測試LinkedList
     System.out.println("------測試LinkedList------");
     list= new LinkedList<String>();
     list.addAll(coll);
     testList(list);
     
     //測試ArrayList
     System.out.println("------測試Vector------");
     list= new ArrayList<String>();
     list.addAll(coll);
     testList(list);
   }
}

運行結(jié)果如圖