仅将 ArrayList 作为值传递而不是引用 [英] Passing ArrayList as value only and not reference

问题描述

简单地说，我有一个带有 ArrayList 参数的方法.在该方法中，我修改 ArrayList 的内容仅用于与该方法返回的内容相关的目的.因此，我根本不希望作为参数传递的 ArrayList 受到影响(即不作为参考传递).

Simply put, I have a method with an ArrayList parameter. In the method I modify the contents of the ArrayList for purposes relevant only to what is returned by the method. Therefore, I do not want the ArrayList which is being passed as the parameter to be affected at all (i.e. not passed as a reference).

我尝试过的一切都没有达到预期的效果.我需要做什么才能仅在方法中使用 ArrayList 的副本，但不能更改实际变量?

Everything I have tried has failed to achieve the desired effect. What do I need to do so that I can make use of a copy of the ArrayList within the method only, but not have it change the actual variable?

推荐答案

即使您有办法将数组列表作为副本传递而不是通过引用传递，它也只是浅拷贝.

Even if you had a way to pass the array list as a copy and not by reference it would have been only a shallow copy.

我会做类似的事情:

void foo(final ArrayList list) {

    ArrayList listCopy = new ArrayList(list);
    // Rest of the code

}

只需处理复制的列表.

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