Error: incompatible types Object Could not be converted [ArrayList]

Question

I am getting a compiler error in my for loop declaration: incompatible types: Object cannot be converted to Type2

I am trying to do this : Java - List of objects. Find object(s) with a certain value in a field

Here is the code:

import java.util.ArrayList;

public class Test2 {
    String name;
    int value;
    public ArrayList list = new ArrayList<Test2>();

    public void q() {
        for(Test2 w : list) { // Here is the error: 'incompatible types: Object cannot be converted to Test2'
            if(w.value == 10)
                System.out.println(w.name);
        }
    }
}

Solution

Java has no way of knowing to expect an object of type Test2 in the list; you need to parameterize it. Either explicitly declare list as public ArrayList<Test2> list = new ArrayList<Test2>();, or cast it in the loop: (Test2 w : (ArrayList<Test2>)list).