数组模拟ArrayList

public class myArrayList {
    String[] a1=new String[5];
    int size;
    //public boolean[] get;
    public void add(String a){
        if (a1.length==size){
            
            String[] temp=new String[a1.length+5];
            System.arraycopy(a1,0,temp,0,a1.length);
            a1=temp;
        }
        a1[size++]=a;
    }
    public int size(){
        return size;
    }
    public String get(int i){
        return a1[i];
    }
}