如何在Java中声明匿名arraylist？

Question

I want to declare anonymous arraylist in java so that on the nature of constructor list can be initialize with any type of object. For example:

    ArrayList<Anonymous> list;

    public AdapterChatWindow(Activity act, ArrayList<CommentData> list, String extras) {        
        this.act = act;     
        this.list = list;
    }

    public AdapterChatWindow(Activity act, ArrayList<ChatHistory> list) {       
        this.act = act; 
        this.list = list;
    }

Is this possible? Any alternate Solution? Is this possible with list type data structure?

Answer 1

You can use a generic type:

public class AdapterChatWindow<T>
{
    ArrayList<T> list;

    public AdapterChatWindow(Activity act, ArrayList<T> list, String extras)
// ....

Then use it like this:

AdapterChatWindow<Foo> acw = new AdapterChatWindow<Foo>(...);

Answer 2

You can go for generic for example..

{List<? extends "your super class"> list;}

now you can initialize your list with any of the subclass of "your super class"

Answer 3

您可以只使用ArrayList<Object> list但是当您想对它们进行任何操作时，都必须仔细转换它们。