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integer和int的区别

更新时间: 2021-06-11 09:55:20     

1、Integer是int的包装类,int则是java的一种基本数据类型 ;

2、Integer变量必须实例化后才能使用,而int变量不需要;

3、Integer实际是对象的引用,当new一个Integer时,实际上是生成一个指针指向此对象;而int则是直接存储数据值;

4、Integer的默认值是null,int的默认值是0。

关键词: integer int 区别

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