手工实现ArrayList 之 增加泛型(2)

版权声明： https://blog.csdn.net/weixin_40072979/article/details/82868853

/**自定义实现一个ArrayList,体会底层原理
 * 增加泛型
 * @author Administrator
 *
 */
public class SxtArrayList02<E> {

	private Object[] elementData;
	private int size;
	
	private static final int DEFAULT_CAPACITY=10;
	
	public SxtArrayList02(){
		elementData =new Object[DEFAULT_CAPACITY];
	}
	
	public SxtArrayList02(int capacity){
		elementData  = new Object[capacity];
	}
	
	public void add(E element){
		elementData[size++] = element;
	}
	
	@Override
	public String toString() {
		StringBuilder sb = new StringBuilder();		
		sb.append("[");
		for(int i=0;i<size; i++){
			sb.append(elementData[i]+",");
		}
		sb.append("]");
		return sb.toString();
	}
	
	public static void main(String[] args) {
		SxtArrayList02 s1 = new SxtArrayList02(20);
		s1.add("aa");
		s1.add("bb");
		
		System.out.println(s1);
	}
}