java 將整型數組轉化爲字符串

java arrays 和arrayList 的區別

package com.vc;

import java.util.Arrays;

public class Demo05 {
    public static void  main(String[] args) {
       int[] arr = {1,2,3,4,5};
       System.out.println(Arrays.toString(arr));
    }
}

public class Demo06 {
    public static void  main(String[] args) {
        List<String> a = new ArrayList<String>();
        a.add("123");
        a.add("456");
        a.add("789");
        int size = a.size();
        String[] array = (String[]) a.toArray(new String[size]);
        System.out.println(array[0]);
        List<String> arrayList = Arrays.asList(array);
        System.out.println(arrayList.get(2));
    }
}