Java, how to remove an Integer item in an ArrayList

Question

Suppose I have such an ArrayList:

ArrayList<Integer> list = new ArrayList<Integer>(); 

After the adding operation:

list.add(2); list.add(3); list.add(5); list.add(7); 

I want to remove number 2, if I do

list.remove(2); 

then number 5 will be deleted, how could I delete number 2? And suppose I don't know the index of number 2.

Answer 1

try this

list.removeAll(Arrays.asList(2)); 

it will remove all elements with value = 2

you can also use this

list.remove(Integer.valueOf(2)); 

but it will remove only first occurence of 2

list.remove(2) does not work because it matches List.remove(int i) which removes element with the specified index