OMG！Java常用类使用总结_程序猿要秃头的博客

import java.util.ArrayList;



public class Test {



    public static void main(String[] args) {



        Object obj1 = new Object();

        Object obj2 = new Object();



        System.out.println(obj1.hashCode()); // 460141958

        System.out.println(obj2.hashCode()); // 1163157884



        String str = new String();

        System.out.println(str.hashCode()); // 0



        ArrayList<Integer> arr = new ArrayList<>();

        System.out.println(arr.hashCode()); // 1

    }

} 


import java.util.ArrayList;



public c