import foo.Nullable; import java.util.ArrayList; import java.util.List; class Foo { void foo1(List<Integer> list) { for (@Nullable Integer i : list) { System.out.println(i.<warning descr="Method invocation 'intValue' may produce 'java.lang.NullPointerException'">intValue</warning>()); } } void foo2(List<@Nullable Integer> list) { for (@Nullable Integer i : list) { System.out.println(i.<warning descr="Method invocation 'intValue' may produce 'java.lang.NullPointerException'">intValue</warning>()); } } void foo3() { List<@Nullable String> list = new ArrayList<>(); list.add(null); for (String s : list) { System.out.println(s.<warning descr="Method invocation 'length' may produce 'java.lang.NullPointerException'">length</warning>()); } } }