我应该定义 class 属性原语（如果可能的话）还是应该使用包装器 class？

Question

I am wondering if it's recommended always to use primitive types such as int when defining class attributes or should I wrapper classes instead of.

class Test{
    private final int id;

    /**
     * Class constructor
     * @param id
     */
    Test(int id) {
      this.id = id;
    }
  }

Answer 1

It depends on what you need to do... If it's important to you to hold null values so you should use wrappers... Else you could as well use primitive... If you don't know if you need null or not then it's better to use primitives to avoid getting NPE.