java数据结构-Vector

1 Vector基础实现为数组 object[] synchronized线程安全

2 扩容使用  System.arraycopy(original, 0, copy, 0,Math.min(original.length, newLength)); native方法

3 add   elementData[elementCount++] = obj;

4  remove elementData[elementCount] = null; /* to let gc do its work */

5 Stack继承自Vector