Say I have a method which has the following signature.

```
 public void processData(Map<String,String> map)

```

Now say this method iterates through a list and calls the below method on each of the item in the list, passing the map it has.

```
public void handle(Map<String,String> map)

```

Now I have checked for null in processData method. If its null it doesn't proceed from there, throwing a custom exception. But should I validate the map for null inside handle method too? Because its already validated in processData method. If its null handle method won't be called. I'm having this doubt because handle method has public visibility. I cannot have it as protected or default as both these methods are in classes of different packages. Any advice would be much appreciated.