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Integer and inner duality?

Can someone explain this to me

 List<Integer> list = new LinkedList<Integer>();
 list.add(2);
 list.add(1);
 list.add(3);

when i used

 list.remove(1);

then the 1st element is deleted

 list.remove(new Integer("1"));

then the 2nd element is deleted.

So you can explain the behavior of automatic boxing and unboxing in the above scenario

when new A().a(new Integer("1"));

performed,

public class A {
    public void test(Integer i) {} //1
    public void test(int i) {} //2
    public void test(Object o) {}//3
}

method 1 is executed

public class A {
    public void test(int i) {} //2
    public void test(Object o) {}//3
}

method 3 adopted

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8 answers

Basically, overload resolution will have a parameter Objectby parameter int, if an argument is presented Integer. (Prefers overloading with a parameter intabove Objector Integer, if represented by an argument int, of course.)

From the JLS section 15.12.2 (with discussion disabled):

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+2
 list.remove(1);

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 list.remove(new Integer("1"));

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. Integer (Integer), ( ).

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(§15.12.2.2) ,

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List provides methods:

public boolean remove(Object o)   // removes the first occurence of this object
public boolean remove(int i)      // removes object stored at index i

If we do list.remove(new Integer(1)), then the best match for this call is the first method (delete the object).

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There are two delete functions in the list:

Although Java does autoboxing (and I believe that if the List.remove (int) method did not exist), the idea here is to determine how to invoke it. Since there is a valid operation with a primitive intthat will be called before any auto-communication occurs.

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