[False Positive][ interprocedural ] is_null_checked test is not that robust about spotbugs HOT 3 OPEN

what I think is like this:
I can give the tool some knowledge:
TextUtils.isEmpty(arg) <-> if (arg == null)
!TextUtils.isEmpty(arg) <-> if (arg != null)

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Hi! I'm a little bit confused as to your report. I'm not sure what bug description you refer to by "is_null_checked". Can you please state exactly the bug being reported by Findbugs / Spotbugs?

As you say, Android's TextUtils.isEmpty return true for both null and empty string. Therefore, a code such as:

String uin = null;
if (android.text.TextUtils.isEmpty(uin)) {
    uin.length(); // This produces a Null Pointer Exception!
}

As such, if it is reporting a null pointer dereference, then the behavior is actually correct.

Could you please clarify? Thanks in advanced

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class TestTextUtils {
  public void foo(String uin){
    if (android.text.TextUtils.isEmpty(uin)){
        System.out.println("do nothing");
        uin.length();  // expected warning here
    } else {
        uin.length();
    }
  }
    
  static boolean isEmpty(String uin){
    if (uin == null || uin.length()==0)
        return true;
    else
        return false;
        
  }
  public void bar(String uin){
    if (isEmpty(uin)){
        System.out.println("do nothing");
        uin.length();   // expected warning here
    } else {
        uin.length();
    }
    
  }
}

sorry, previous example is not that correct.. you can refer to below code..
Checking this code, Findbugs doesn't find anything..

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