Arrlist的重要方法重写

 import java.util.Arrays;

 public class ArrayOperator {

     public static void main(String[] args) {
         // TODO Auto-generated method stub
  ArrList list = new ArrList();
   list.add(5);
   list.add(7);
   list.add(6);
   System.out.println(list.sizeof());
 //  list.remove(0);
 list.insert(1, 7);
 System.out.println(list.toString());
 System.out.println(list.search(6));

     }

 }
 class ArrList{
     //定义元素个数
     private int size =  0;
     //初始定义数组
     private int[] data = new int[10];
     public ArrList(){
     }
     public ArrList(int inificapacity){ //初始化数组容量的构造方法
         if(inificapacity < 0){
             throw new ArrayIndexOutOfBoundsException();
         }else {
             data = new int[inificapacity];
         }
     }
     public boolean isEmpty(){ //判断数组是否为空操作
         return size ==0;
     }
     public  void grow(){ //判断元素是否需要扩容
         if(data.length <=1){
             data = Arrays.copyOf(data, data.length+1);
         }else{
             data = Arrays.copyOf(data, data.length+data.length>>1);
         }

     }
     public void add(int element){ //增加元素操作
         if(size >= data.length){
             this.grow();
         }else{
             data[size++] = element;
         }
     }
     public  void insert(int index,int element){ //插入元素操作
         if(index < 0){
             throw new ArrayIndexOutOfBoundsException();
         }else if(index <= size){
             for(int i = size-1; i >= index;i--){
                  data[i+1] = data[i];
             } data[index] = element;
             size++;

         }else{
             throw new ArrayIndexOutOfBoundsException();
         }
     }
     public  void remove(int index){
         if(index < 0){
             throw new ArrayIndexOutOfBoundsException();
         }
         else if(index < size){
             for(int i = index; i < data.length-1;i++){
                 data[i] = data[i+1];
             }size--;
         }else{
             throw new ArrayIndexOutOfBoundsException();
         }
     }
     public int search(int element){

         for(int i = 0; i < size;i++){
             if(data[i] == element){

                 return i;
             }
         }
         return -1;
     }
     public  int ele(int index){
         if(index < 0 || index >= size){
             throw new ArrayIndexOutOfBoundsException();
         }else{
             return data[index];
         }
     }
     public  int sizeof(){
         return size;
     }
     public  void clear(){
         data = new int[10];
         size = 0;
     }
     @Override
     public String toString(){
         StringBuilder str = new StringBuilder("[");
         for(int i = 0 ;i < size ;i++){
             str.append(data[i]).append(",");
         }
         String sb = str.toString();
         if(size > 0){
             sb= sb.substring(0,sb.length()-1);
         }
         return sb + "]";
     }
     }