@ByoungJoonIm Feel free to send us a PR that fixes this. Hi I made a pr that fixes this, thank you
Function name is incorrect.
I saw [DoAnswerStyleStubbing](https://github.com/mockito/mockito/blob/96eb5e0cbff80a1545b1093db1baf4e33a2041e7/src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java#L27-L29) class code.
I thought that below is correct.

```java
boolean isSet() {
    return !answers.isEmpty();
}
```
After execute `setAnswers` function with answers, instance will return `isSet is false`.
I think it looks strange.

And [InvocationContainerImpl](https://github.com/mockito/mockito/blob/96eb5e0cbff80a1545b1093db1baf4e33a2041e7/src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java#L112-L114) also need to be changed as follow.
```java
public boolean hasAnswersForStubbing() {
    return doAnswerStyleStubbing.isSet();
}
```
src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java
src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java
diff --git a/src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java b/src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java
index e143379362..c15fc025b4 100644
--- a/src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java
+++ b/src/main/java/org/mockito/internal/stubbing/DoAnswerStyleStubbing.java
@@ -25,7 +25,7 @@ void setAnswers(List<Answer<?>> answers, Strictness stubbingStrictness) {
     }
 
     boolean isSet() {
-        return answers.isEmpty();
+        return answers.size() > 0;
     }
 
     void clear() {
diff --git a/src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java b/src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java
index 832b1b155b..927d230e0f 100644
--- a/src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java
+++ b/src/main/java/org/mockito/internal/stubbing/InvocationContainerImpl.java
@@ -110,7 +110,7 @@ public void setAnswersForStubbing(List<Answer<?>> answers, Strictness strictness
     }
 
     public boolean hasAnswersForStubbing() {
-        return !doAnswerStyleStubbing.isSet();
+        return doAnswerStyleStubbing.isSet();
     }
 
     public boolean hasInvocationForPotentialStubbing() {
