java线性表尝试实现

package bjsxt.collection;

/*
 * 实现ArrayList的部分方法
 */
public class TestArrayList {
	private Object[] elementData; //初始化数组
	
	private int size; //数组里元素的数量
	
	public int size() {
		return size;
	}
	
	public TestArrayList() {  //默认数组长度
		this(10);
	}
	
	public TestArrayList(int initialCapacity) {
		if(initialCapacity<0) {
			try {
				throw new Exception();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		elementData=new Object[initialCapacity];
	}
	
	public void add(Object obj) {
		//数组扩容和数据的拷贝
		if(size==elementData.length) {
			Object[] newArray=new Object[size+1];
			for(int i=0;i<size;i++) {
				newArray[i]=elementData[i];
			}
			elementData=newArray;
		}
		elementData[size++]=obj;
	}
	
	public boolean isEnpty() {
		return size==0;
	}
	
	public Object get(int index) {
		if(index<0||index>=size) {
			try {
				throw new Exception();
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return elementData[index];
	}
	
	public void remove(int index) {
		//删除指定位置的对象
		RangeCheck(index);
		for(int i=index;i<size-1;i++) {
			elementData[i]=elementData[i+1];
		}
		elementData[--size]=null;
	}
	
	public void RangeCheck(int index) {
		if(index<0||index>=size) {
			try {
				throw new Exception();
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	public static void main(String[] args) {
		TestArrayList list=new TestArrayList(3);
		list.add("333");
		list.add("333");
		list.add("333");
		list.add("333");
		System.out.println(list.size());
		System.out.println(list.isEnpty());
		System.out.println(list.get(2));
		list.remove(3);
	}
}

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转载自blog.csdn.net/weixin_42230478/article/details/82857649
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