1、LinkedList與ArrayList的區別

1）、LinkedList是基於鏈表的數據結構，ArrayList是實現了基於動態數組的數據結構；

2）、對於查詢(get)，ArrayList比LinkedList效率高，因為LinkedList要移動指針

對於新增(insert)和刪除(remove)，LinkedList比ArrayList效率高，因為ArrayList要移動數據

代碼如下：

public class ComporeTest {

    private  static Logger logger = LoggerFactory.getLogger(ComporeTest.class);
    private static Integer N = 5000;

    public static Long timeList(List list){
        Long start = System.currentTimeMillis();
        logger.info("start{}",start);
        for(int i = 0; i < N; i++){
            list.add(i);
        }
        logger.info("timeList{}",System.currentTimeMillis() - start);
        return System.currentTimeMillis() - start;
    }

    public static List  addList(List list){
        Object o = new Object();
        for(int i = 0;i < N; i++){
            list.add(0,o);
        }
        logger.info("測試ArrayList與LinkedList的效率");
        return list;
    }

    static Long readList(List list){
        long start = System.currentTimeMillis();
        for(int i = 0; i < list.size(); i++){
            list.get(i);
        }
        return System.currentTimeMillis() - start ;
    }

    public static void main(String [] args){
        logger.info("ArrayList添加"+N+"條消耗時間：{}",timeList(new ArrayList()));
        logger.info("LinkedList添加"+N+"條消耗時間：{}",timeList(new LinkedList()));
        List arrayList = addList(new ArrayList<>()) ;
        List linkedList = addList(new LinkedList<>());
        logger.info("ArrayList查詢"+N+"消耗時間：{}",readList(arrayList));
        logger.info("LinkedList查詢"+N+"消耗時間：{}",readList(linkedList));
    }
}
測試結果：

java學習過程的簡單記錄