定义一个泛型类MyArrayList，实现数组列表的基本操作: add、remove、get、size

public class MyArrayList<T> {
    private Object[] array;
    private int size;

    public MyArrayList() {
        this.array = new Object[10];
        this.size = 0;
    }

    public void add(T element) {
        if (size == array.length) {
            Object[] newArray = new Object[array.length * 2];
            System.arraycopy(array, 0, newArray, 0, size);
            array = newArray;
        }
        array[size++] = element;
    }

    public void remove(int index) {
        if (index < 0 || index >= size) {
            throw new IndexOutOfBoundsException();
        }
        System.arraycopy(array, index + 1, array, index, size - index - 1);
        array[--size] = null;
    }

    public T get(int index) {
        if (index < 0 || index >= size) {
            throw new IndexOutOfBoundsException();
        }
        return (T) array[index];
    }

    public int size() {
        return size;
    }
}

使用示例：

MyArrayList<String> list = new MyArrayList<>();
list.add("foo");
list.add("bar");
list.add("baz");
System.out.println(list.get(1)); // 输出 "bar"
list.remove(0);
System.out.println(list.size()); // 输出 2